Boat Thruster Guide

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Thruster specs

VETUS Bow 55 Ignition Protected: specs, price and boat fit

If your boat runs on gasoline, the Bow 55 Ignition Protected lets you fit a bow thruster without bringing an open spark into a space that may hold fuel vapor. The motor is enclosed in a gasketed housing. Push is 121 to 132 lb, the higher figure on 24 V, for boats of roughly 26 to 39 ft.

US dealers ask $2,610, compared with $2,137 for the regular Bow 55, and the 12 V and 24 V versions sell at one price. Add about $451 to $990 for the tube, helm panel, main switch and fuse. Its manual wants that switch and fuse inside a closed box, since they can spark as well. Our battery, cable and charging estimate: $586 to $820.

The motor inside is still brushed, so plan a yearly look at the brushes and a new zinc. Skip copper-based bottom paint on the unit. A VETUS dealer should handle the routine service to keep the three-year warranty valid. See what else you’ll need.

The full spec sheet for a yard sits lower down, and the VETUS thruster review covers VETUS’s whole range.

Where this summary comes from (4 sources, read 12 October 2026)

Choose a size

The VETUS Bow 55 Ignition Protected comes in two sizes. Each has its own price, wiring and boats it suits, so pick one and the facts, the fit, the cost and the spec sheet below show that size.

Every size of the VETUS Bow 55 Ignition Protected side by side, from the database. The figures are VETUS’s and the dealers’.
SizePushVoltageVETUS’s boat lengthPrice
Bow 55 Ignition Protected at 12 V 121 lb (55 kgf) 12 V 26 to 39 ft $2,610
Bow 55 Ignition Protected at 24 V 132 lb (60 kgf) 24 V 26 to 39 ft $2,610

Key facts

  • DIY level 2 of 5 Wiring prep only
  • Thrust 121 lb 55 kgf, VETUS's rating
  • Boat length 26 to 39 ft VETUS's own range
  • Price $2,610 equipment only, defender.com, 28 August 2026
  • Fitted by a yard $9,387 to $11,870 Our estimate at 35 ft, unit and job
  • Voltage 12 V As sold
  • Mounts Tunnel Fixed mount, bow
  • To fit it Haul-out The boat comes out of the water
  • Run limit 4 min Of continuous use at 12 V

Every figure here is the maker’s or a dealer’s, except the fitted cost, which is our estimate. The full spec sheet is further down.

How much of the install is yours

DIY 2 of 5: Wiring prep only. The yard fits the unit and does the hull work; you do the wiring prep.

DIY levels

  • Level 5: Owner install. No yard, no electrician.
  • Level 4: You fit it, electrician connects. You mount and wire it; a marine electrician makes the final connections.
  • Level 3: Split with the yard. The yard does the below-waterline part; you do the wiring.
  • Level 2: Wiring prep only. The yard fits the unit and does the hull work; you do the wiring prep.
  • Level 1: Yard job. A qualified professional does all of it.

You Yard Electrician. The bar is labor hours; a haul-out is a note.

How we rate DIY

You: 4 to 16 h Yard: 32 to 70 h Electrician: 2 to 4 h Plus a haul-out.

  1. Cut, bond and fair the tunnel; fit the gear leg, motor and propeller Yard 32 to 70 h The low end is two crew over two days, the job as owners describe it on the forums. The high end rises with boat length between two real billed figures: 32 hours at 35 ft, and the largest invoice we hold, 70 hours at 47 ft.
  2. Mount the battery box, switch and fuse holder; run and secure the cables You 4 to 16 h Our estimate. No maker times this step, and a first-time owner is slower than a yard, so the range is wide.
  3. Final connections at the battery and the motor, load test Electrician 2 to 4 h Our estimate. Nobody publishes a time for the final connections and test on their own.

Your part needs:Heavy battery cableCrimping big lugs

A qualified marine electrician should make the final connections and test them before first use. Hours are labor only.

Is it right for your boat?

What VETUS says 26 to 39 ft The maker's own range, from its listing
What our sizing says 37 to 42 ft Full thrust in 15 knots. The longest boat of each kind is in the table.

Our figure is the longest boat one unit can steer in a 15 knot wind. It is a range because each kind of boat catches the wind differently. Here a sailboat gets full thrust to 37 ft, and a catamaran to 42 ft. The maker gives one range for every boat.

The table below tries the VETUS Bow 55 Ignition Protected on each kind of boat, at every length that kind of boat is built in. The wind is 15 knots and the rules are the finder’s own. A length counts as a fit when the unit gives the thrust that boat needs at the bow and the maker lists it for that length.

A boat up to 10 percent past the maker’s range still counts here, as it does in the finder. So the table runs up to 42 ft, just past VETUS’s own range (26 to 39 ft).

The VETUS Bow 55 Ignition Protected against each kind of boat, in a 15 knot wind. Our sizing, from the finder’s own rules.
Boat Full thrust at 15 knotsStill a fit, in lighter wind
Pontoon & tritoon Not listed. A pontoon has no hull body between the logs to bore a tunnel through, and nobody sells one for these boats.
Sailboat 31 to 37 ft 38 to 42 ftfull thrust to about 13 knots at 42 ft
Houseboat None 30 to 40 ftfull thrust to about 10 knots at 40 ft
Catamaran 35 to 42 ft None
Trawler 31 to 37 ft 38 to 42 ftfull thrust to about 13 knots at 42 ft
Motor yacht 35 to 37 ft 38 to 42 ftfull thrust to about 13 knots at 42 ft
Bass & flats Not listed. Nobody sells a tunnel kit for these hulls, and a bass boat’s shallow planing bow has almost no depth to hold one.
Wake & ski boats Not listed. Nobody sells a tunnel kit for these hulls.
Express cruiser 39 to 42 ft None
Center console No length. More thrust than the boat needs.

Reading the two length columns. The first column is where one unit gives all the thrust the boat needs in 15 knots. The second is where the finder still lists it: the unit falls short of what the boat needs by no more than 10 percent, and gives the whole figure only in the lighter wind named. On a boat shorter than the first column’s shortest length, the unit is more than the boat needs.

It is sized for six kinds of boat here. For your own boat, the finder gives an answer that also counts your drive and who does the fitting. The compare page sets this unit beside others.

What it costs fitted

These totals are our estimate of a yard job: the unit’s price, plus a yard’s hours at $160 to $180 an hour, plus the batteries, cable and charger, plus the other parts the box does not hold. A Lifting the boat out of the water on a travel lift or a trailer so work can be done below the waterline. It is billed separately from the job itself. adds $540 to $2,030 at these lengths, with 5 to 7 days out of the water, worked from eight yards’ own rate cards. The hours come from what owners and yards report. Your own yard will have its own opinion. The cost page builds the same figures line by line.

The VETUS Bow 55 Ignition Protected fitted by a yard, from the shortest to the longest boat it is sized for. Our estimate.
Boat length The unit Yard labor Haul-out Batteries, cable, charger Other parts Total
30 ft $2,610 $5,120 to $5,760about 32 hours $540 to $1,450 $586 to $820 $451 to $990 $9,307 to $11,630
35 ft $2,610 $5,120 to $5,760about 32 hours $620 to $1,690 $586 to $820 $451 to $990 $9,387 to $11,870
42 ft $2,610 $5,120 to $9,72032 to 54 hours $750 to $2,030 $586 to $820 $451 to $990 $9,517 to $16,170

How the batteries, cable and charger add up. We price a battery bank close to the thruster, as the makers recommend, with 10 to 20 ft of cable out and back: red for the positive, black for the negative, cut to length. The low end is the cheapest battery that meets the figure and the shorter run; the high end is a sealed (AGM) battery and the longer run. The charger is a NOCO GEN5X2 two-bank shore charger.

Batteries and lugs are priced at Fisheries Supply and the cable and charger at Defender, read 12 October 2026.

  • At 12 V: one 12 V battery, at least 625 CCA (VETUS’s minimum), $360 for the battery; VETUS’s cable table gives 1 to 3/0 AWG, priced on 1 to 4/0 AWG, the nearest size cut to length: $80 to $314 for the red and black cable and the lugs; a GEN5X2 charger, $146.

The sizing and the costs on this page are estimates, for guidance only and without warranty. They are no quote, and nobody has inspected your boat. Check them against the maker’s manual and your yard before you rely on them. Terms of use.

Key facts

  • DIY level 2 of 5 Wiring prep only
  • Thrust 132 lb 60 kgf, VETUS's rating
  • Boat length 26 to 39 ft VETUS's own range
  • Price $2,610 equipment only, defender.com, 28 August 2026
  • Fitted by a yard $9,540 to $11,850 Our estimate at 35 ft, unit and job
  • Voltage 24 V As sold
  • Mounts Tunnel Fixed mount, bow
  • To fit it Haul-out The boat comes out of the water
  • Run limit Not published Ask the maker before long use

Every figure here is the maker’s or a dealer’s, except the fitted cost, which is our estimate. The full spec sheet is further down.

How much of the install is yours

DIY 2 of 5: Wiring prep only. The yard fits the unit and does the hull work; you do the wiring prep.

DIY levels

  • Level 5: Owner install. No yard, no electrician.
  • Level 4: You fit it, electrician connects. You mount and wire it; a marine electrician makes the final connections.
  • Level 3: Split with the yard. The yard does the below-waterline part; you do the wiring.
  • Level 2: Wiring prep only. The yard fits the unit and does the hull work; you do the wiring prep.
  • Level 1: Yard job. A qualified professional does all of it.

You Yard Electrician. The bar is labor hours; a haul-out is a note.

How we rate DIY

You: 4 to 16 h Yard: 32 to 70 h Electrician: 2 to 4 h Plus a haul-out.

  1. Cut, bond and fair the tunnel; fit the gear leg, motor and propeller Yard 32 to 70 h The low end is two crew over two days, the job as owners describe it on the forums. The high end rises with boat length between two real billed figures: 32 hours at 35 ft, and the largest invoice we hold, 70 hours at 47 ft.
  2. Mount the battery box, switch and fuse holder; run and secure the cables You 4 to 16 h Our estimate. No maker times this step, and a first-time owner is slower than a yard, so the range is wide.
  3. Final connections at the battery and the motor, load test Electrician 2 to 4 h Our estimate. Nobody publishes a time for the final connections and test on their own.

Your part needs:Heavy battery cableCrimping big lugs

A qualified marine electrician should make the final connections and test them before first use. Hours are labor only.

Is it right for your boat?

What VETUS says 26 to 39 ft The maker's own range, from its listing
What our sizing says 38 to 42 ft Full thrust in 15 knots. The longest boat of each kind is in the table.

Our figure is the longest boat one unit can steer in a 15 knot wind. It is a range because each kind of boat catches the wind differently. Here a trawler gets full thrust to 38 ft, and a catamaran to 42 ft. The maker gives one range for every boat.

The table below tries the VETUS Bow 55 Ignition Protected on each kind of boat, at every length that kind of boat is built in. The wind is 15 knots and the rules are the finder’s own. A length counts as a fit when the unit gives the thrust that boat needs at the bow and the maker lists it for that length.

A boat up to 10 percent past the maker’s range still counts here, as it does in the finder. So the table runs up to 42 ft, just past VETUS’s own range (26 to 39 ft).

The VETUS Bow 55 Ignition Protected against each kind of boat, in a 15 knot wind. Our sizing, from the finder’s own rules.
Boat Full thrust at 15 knotsStill a fit, in lighter wind
Pontoon & tritoon Not listed. A pontoon has no hull body between the logs to bore a tunnel through, and nobody sells one for these boats.
Sailboat 32 to 39 ft 40 to 42 ftfull thrust to about 14 knots at 42 ft
Houseboat None 30 to 42 ftfull thrust to about 10 knots at 42 ft
Catamaran 37 to 42 ft None
Trawler 32 to 38 ft 39 to 42 ftfull thrust to about 14 knots at 42 ft
Motor yacht 35 to 38 ft 39 to 42 ftfull thrust to about 14 knots at 42 ft
Bass & flats Not listed. Nobody sells a tunnel kit for these hulls, and a bass boat’s shallow planing bow has almost no depth to hold one.
Wake & ski boats Not listed. Nobody sells a tunnel kit for these hulls.
Express cruiser 41 to 42 ft None
Center console No length. More thrust than the boat needs.

Reading the two length columns. The first column is where one unit gives all the thrust the boat needs in 15 knots. The second is where the finder still lists it: the unit falls short of what the boat needs by no more than 10 percent, and gives the whole figure only in the lighter wind named. On a boat shorter than the first column’s shortest length, the unit is more than the boat needs.

It is sized for six kinds of boat here. For your own boat, the finder gives an answer that also counts your drive and who does the fitting. The compare page sets this unit beside others.

What it costs fitted

These totals are our estimate of a yard job: the unit’s price, plus a yard’s hours at $160 to $180 an hour, plus the batteries, cable and charger, plus the other parts the box does not hold. A Lifting the boat out of the water on a travel lift or a trailer so work can be done below the waterline. It is billed separately from the job itself. adds $540 to $2,030 at these lengths, with 5 to 7 days out of the water, worked from eight yards’ own rate cards. The hours come from what owners and yards report. Your own yard will have its own opinion. The cost page builds the same figures line by line.

The VETUS Bow 55 Ignition Protected fitted by a yard, from the shortest to the longest boat it is sized for. Our estimate.
Boat length The unit Yard labor Haul-out Batteries, cable, charger Other parts Total
30 ft $2,610 $5,120 to $5,760about 32 hours $540 to $1,450 $739 to $800 $451 to $990 $9,460 to $11,610
35 ft $2,610 $5,120 to $5,760about 32 hours $620 to $1,690 $739 to $800 $451 to $990 $9,540 to $11,850
42 ft $2,610 $5,120 to $9,72032 to 54 hours $750 to $2,030 $739 to $800 $451 to $990 $9,670 to $16,150

How the batteries, cable and charger add up. We price a battery bank close to the thruster, as the makers recommend, with 10 to 20 ft of cable out and back: red for the positive, black for the negative, cut to length. The low end is the cheapest battery that meets the figure and the shorter run; the high end is a sealed (AGM) battery and the longer run. The charger is a NOCO GEN5X2 two-bank shore charger.

Batteries and lugs are priced at Fisheries Supply and the cable and charger at Defender, read 12 October 2026.

  • At 24 V: two 12 V batteries in series, at least 342 CCA each (VETUS’s minimum), $513 for both; VETUS’s cable table gives 2 AWG, priced on 1 AWG, the nearest size cut to length: $80 to $141 for the red and black cable and the lugs; a GEN5X2 charger, $146.

The sizing and the costs on this page are estimates, for guidance only and without warranty. They are no quote, and nobody has inspected your boat. Check them against the maker’s manual and your yard before you rely on them. Terms of use.

What else you buy

What follows comes from VETUS’s BOW55D installation manual 020522.11 r08 and the BOW PRO Boosted manual 020808.04 r09, May 2026 and February 2026, read 30 September 2026.

In the box
The unit assembled or in parts, the zinc anode, insulated gaskets, the drill template, the solenoid switches and the 5 A control fuse on the motor. BOW PRO: the thruster fuse in the connection unit.
Bought separately
The tunnel, the main switch (BATSW250 or BATSW600), the main fuse (ZE) and holder (ZEHC100), the cable, the control panel and its cable.
Charging
Every VETUS manual wants "its own separate battery or batteries" near the thruster, sealed if it shares the motor's compartment. The BOW PRO Boosted units carry a charger (12 V, 80 A) fed from the boat's bank, with a fused feed cable. The other manuals show an alternator and a battery separator on the wiring diagram and say nothing more.

The manual’s words, page 22 of the Boosted manual: “By connecting the 24 Volt battery bank to the MCVB boosted charge connection, the 48 Volt, battery bank is charged. An additional charging facility is not required.”

The “other parts” line in the estimate above is the priced parts below, $451 to $990 at Fisheries Supply’s prices on 30 September 2026. The batteries, cable and charger have a line of their own.

Parts the VETUS Bow 55 Ignition Protected’s box leaves to you, from the makers’ manuals read 30 September 2026. “What to ask for” is VETUS’s own part or model where its manual names one, otherwise the dealer’s item.
Part What it is What to ask for Dealer price
Tunnel tube The fiberglass, aluminum or steel pipe the thruster sits in, bonded through the bow. BP150G75, BP150G10, BP150G15 (30 in, 40 in, 60 in) $122–$186150 mm fiberglass tunnel tubes up to 60 in (1.5 m) long (VETUS), at Fisheries Supply, read 16 October 2026.
Control panel The buttons or joystick at the helm. One helm, one panel: a second steering station needs a panel of its own. BPSE2 push buttons, BPJSTA joystick, BPJE2 or EZDOCK2 $219–$374Side-Power touch panel and single joystick, VETUS push-button panel, Lewmar single joystick, at Fisheries Supply.
Control cable, panel to motor The thin cable from the helm to the motor. Sold by length. VETUS panel cable, by length $29–$173Side-Power control cables, VETUS panel cables, Lewmar Gen 2 connecting cables, at Fisheries Supply.
Main fuse A slow-blow fuse of the ANL type at the battery, in the size the maker prints for the model. ZE series slow-blow, the rating in the yard table below $18–$57Side-Power ANL fuses, Blue Sea ANL fuses, at Fisheries Supply, read 16 October 2026.
Fuse holder The block the ANL fuse bolts into, with a cover. ZEHC100 $27–$93Egis and Blue Sea ANL fuse blocks, Side-Power ANL fuse holders, at Fisheries Supply, read 16 October 2026.
Main battery switch The switch that cuts the thruster off from its battery when you leave the boat. BATSW250 (BATSW600 on the bigger units), or BPMAIN12/24 for a remote switch $35–$107Egis m-Series 300 A, Blue Sea e-Series 350 A and HD-Series 600 A on/off switches, at Fisheries Supply, read 16 October 2026.
Battery cable and lugs The two heavy cables from the battery to the motor, sized to the length of the run. The wiring calculator sizes them. VETUS names none In the electrical line
Battery bank A cranking-type bank near the motor, sized by the maker's cold cranking amps. The battery calculator checks it. VETUS names none In the electrical line
Charger or charge feed How the thruster bank gets charged: a shore charger of its own, a DC-to-DC charger or charging relay from the boat's system, or a charger built into the unit. VETUS names none $146–$305NOCO GEN5X2 shore charger, Victron Orion-Tr Smart DC-DC charger, Blue Sea ML-ACR charging relay, at Fisheries Supply.
Glass, resin, filler and sealant What bonds the tube or housing into the hull and seals the gear leg. VETUS names none Not priced

The cost page has the whole list with what every maker says about each part.

For the yard and the installer

The full spec sheet, grouped the way a yard reads it. Every figure is the maker’s or a dealer’s, with its source.

The VETUS Bow 55 Ignition Protected, every published figure the site holds, with where each came from.
Thrust and motor
Thrust 121 lb (55 kgf) As printed: Thrust (in lbs force): 121
Voltage12 V
Fitting
TypeTunnel, fixed mount
End of the boatBow
Tunnel diameter150 mm
What it does to the hullTunnel bore below the waterline
Haul-out to fit itYes
Maker’s boat length26 to 39 ft
Price and ordering
Price $2,610 equipment only, a dealer's price, defender.com, 28 August 2026
Part number BOW5512I12 V
BOW5524I24 V
Documents
Manual Installation manual (PDF)on the maker's site
Warranty VETUS gives 3 years, or 1 for professional use, and it transfers to the next owner. Claims go through the dealer only. It is void unless an authorized VETUS dealer does the periodic maintenance, and transport, labor and lifting are excluded. VETUS's warranty policy
The site’s reviewVETUS thruster review

Draw, cable, fuse and battery, at each voltage

These are the maker’s own figures, at each voltage it is sold at. The cable is the size for the shortest run in the maker’s table. A longer run may need heavier cable, and the wiring calculator works that out for your own boat.

The VETUS Bow 55 Ignition Protected’s draw, cable, fuse, battery and run limit, as the maker publishes them.
Voltage Draw Maker’s cable Fuse Battery Run limit
12 V 375 Anominal draw 2 AWG for up to 7 ft of cable counted out and back. Longer runs take heavier cableinstallation manual 020522.11, r08, May 2026 250 Ainstallation manual 020522.11, r08, May 2026 625 CCA minimum, 1,250 CCA maximumVETUS installation manual 020522.11, r08, May 2026 4 min of continuous use at 12 Vinstallation manual 020522.11, r08, May 2026

For the yard and the installer

The full spec sheet, grouped the way a yard reads it. Every figure is the maker’s or a dealer’s, with its source.

The VETUS Bow 55 Ignition Protected, every published figure the site holds, with where each came from.
Thrust and motor
Thrust 132 lb (60 kgf) As printed: Thrust (in lbs force): 132
Voltage24 V
Fitting
TypeTunnel, fixed mount
End of the boatBow
Tunnel diameter150 mm
What it does to the hullTunnel bore below the waterline
Haul-out to fit itYes
Maker’s boat length26 to 39 ft
Price and ordering
Price $2,610 equipment only, a dealer's price, defender.com, 28 August 2026
Part number BOW5512I12 V
BOW5524I24 V
Documents
Manual Installation manual (PDF)on the maker's site
Warranty VETUS gives 3 years, or 1 for professional use, and it transfers to the next owner. Claims go through the dealer only. It is void unless an authorized VETUS dealer does the periodic maintenance, and transport, labor and lifting are excluded. VETUS's warranty policy
The site’s reviewVETUS thruster review

What holds up and what to weigh

Each point names the fact it rests on.

What holds up

  • It is sold at 12 V and at 24 V.The maker's and dealers' listings

What to weigh

  • The boat comes out of the water to fit it: it needs a tunnel bore below the waterline.The mounting: a bore through the hull, or a housing recessed into it

What the manual and listings say

This is the note we keep on the VETUS Bow 55 Ignition Protected, written from the maker’s manual, its product pages and the dealer’s listing.

In the box: The solenoid switches and the 5 A control fuse are on the motor. The panel, its cable, the main fuse and switch are bought.

12 V

The ignition-protected build, with a sealed motor for a gasoline boat where the thruster shares a space with fuel, an engine or a tank. Same 150 mm tunnel as the standard BOW55. Defender prices it above the standard unit. The motor is brushed, and its brushes and anode are checked yearly. No copper-based antifouling goes on the unit.

Defender sells the 12 V and 24 V versions as one listing at one price. The warranty runs three years and is claimed through the dealer only. It is void unless an authorized VETUS dealer does the periodic maintenance, and labor, transport and lifting are excluded.

24 V

The 24 V build, on two 12 V batteries in series, in the standard BOW55's 150 mm tunnel.

Videos

Two of VETUS’s own videos, from its YouTube channel: how VETUS picks a size, a battery bank and a panel, and the first of its service videos for a tunnel unit. They are the maker’s pitch. Watch them for what the unit looks like and how it goes in, and take any claim back to the figures above.

VETUS’s own video, on VETUS’s YouTube channel. The picture is a still from it.
VETUS’s own video, on VETUS’s YouTube channel. The picture is a still from it.

Other sizes and close alternatives

VETUS also sells this thrust built another way. Each has its own page:

These are VETUS’s next sizes in the same line, by thrust.

These are other makers’ units of the same style, for the same end, within a quarter of its published thrust. Each is that maker’s nearest match.

Compare them side by side

Every model with a page here is listed, maker by maker, on the thruster index.

Where to go next

The specs are the maker’s and the dealers’, on the dates shown. The sizing and the costs are our arithmetic, done without seeing your boat.