Boat Thruster Guide

What to buy, what it costs, what it takes to fit

We may earn a referral commission from some links on this page. It doesn't change your price or our recommendations.

Thruster specs

VETUS STE9512D: specs, price and the boats it fits

The STE9512D is the strongest of VETUS’s four swing-down thrusters, with 214 lb of push on 12 V. It stays tucked in a hull housing until you switch it on, then swings into the water, which keeps the bottom clean and fast when you’re underway. It works at the bow or the stern.

Not sold in the US right now. No US store or distributor lists the VETUS STE9512D: we checked Defender, Fisheries Supply and Citimarine on October 15, 2026. Its specs and parts stay here for owners of boats built or bought abroad. For one to buy here, see the models on the VETUS thruster review that have a US price.

VETUS quotes this one through its dealers. Because the housing is built into the hull, the boat comes out of the water and the yard bill runs higher than for a tunnel unit. Around it you’ll buy a control panel, a main switch, a fuse and holder, about $328 to $803, and a nearby battery with cable and charging, about $769 to $1,101. Jump to the parts list.

It’s rated for 3 minutes of running at a time. You get a short pause on each direction change and an automatic stow after 15 minutes left down. The brushed motor needs a yearly brush and zinc check; the warranty is three years via the dealer.

Fitting it yourself? The installer section has every spec, and the VETUS thruster review sets this model against the rest of the VETUS range.

Where this summary comes from (5 sources, read 12 October 2026)

Key facts

  • DIY level 2 of 5 Wiring prep only
  • Thrust 214 lb 97 kgf, VETUS's rating
  • Boat length Not published See our sizing below
  • Price No US price None is published, so there is no fitted cost to work out
  • Fitted by a yard No total No price to build on
  • Voltage 12 V As sold
  • Mounts Retractable Drops down, bow or stern
  • To fit it Haul-out The boat comes out of the water
  • Run limit 3 min At a stretch, the manual's S2 rating

Every figure here is the maker’s or a dealer’s. No US price is published, so there is no fitted cost to 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: 40 to 88 h Electrician: 2 to 4 h Plus a haul-out.

  1. Cut the hull and fit the housing and mechanism Yard 40 to 88 h Nobody publishes an hours figure. Fisheries Supply says installation is significantly more expensive than a tunnel, and that is too loose to turn into a number. So this is the tunnel’s own banded figure plus a quarter, which keeps it above a tunnel as the distributors describe it.
  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 No boat length Our sizing is the guide here
What our sizing says 36 to 62 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 houseboat gets full thrust to 36 ft, and an express cruiser to 62 ft.

The table below tries the VETUS STE9512D 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. VETUS publishes no boat length, so thrust alone decides.

The VETUS STE9512D 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 retractable drops down inside the hull, and a pontoon has no hull depth to drop into.
Sailboat 41 to 49 ft 50 to 73 ftfull thrust to about 10 knots at 73 ft
Houseboat 31 to 36 ft 37 to 54 ftfull thrust to about 10 knots at 54 ft
Catamaran 46 to 56 ft 57 to 80 ftfull thrust to about 11 knots at 80 ft
Trawler 41 to 48 ft 49 to 73 ftfull thrust to about 10 knots at 73 ft
Motor yacht 41 to 48 ft 49 to 73 ftfull thrust to about 10 knots at 73 ft
Bass & flats Not listed. A retractable needs hull depth to drop into, and these planing hulls have almost none forward.
Wake & ski boats Not listed. A retractable needs hull depth to drop into, and these planing hulls have almost none forward.
Express cruiser 52 to 62 ft 63 to 65 ftfull thrust to about 14 knots at 65 ft
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

No US dollar price is published for the VETUS STE9512D, so we build no total for it. The yard’s share of the job is on the cost page.

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 retractable thruster installation instructions 020584.05 r02, December 2024, read 12 October 2026.

In the box
The STE manual prints no list of what comes in the box. It does say the template for cutting the hull opening is not provided: you make one from scrap sheet or stiff cardboard. Its technical data puts the 5 A control fuse and the relay on the unit.
Bought separately
A main switch on the positive cable (a VETUS battery switch, or the BPMAIN12 remote main switch), a fuse on the positive cable and its holder (ZEHC100), the battery cable, the control panel and its cable.
Charging
The STE manual wants the unit on its own battery or batteries, close by so the cables stay short, and sealed batteries (VETUS SMF or AGM) if they share its compartment, because sparks from the motor brushes can light the gas an open battery gives off while charging. How that battery is charged it leaves to you and your installer.

The manual’s words, page 35: “We also recommend that each bow thruster is powered by its own separate battery or batteries.”

A yard job adds these parts on top of the unit: $328 to $803 for the priced ones below, at Fisheries Supply’s prices on 30 September 2026, plus the batteries, cable and charger.

Parts the VETUS STE9512D’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
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 STE9512D, every published figure the site holds, with where each came from.
Thrust and motor
Thrust 214 lb (97 kgf) As printed: Rated thrust : 950 N (95 kgf, 214 lbf ) (installation manual 020584.05 r02 (December 2024), technical data, read 2026-10-12)
Motor5.7 kW
Voltage12 V
Fitting
TypeRetractable, drops down
End of the boatBow or stern
Tunnel diameter185 mm
What it does to the hullLarge hull opening below the waterline
Haul-out to fit itYes
Maker’s boat lengthNot published
Price and ordering
Price No US price published
Part number STE9512D12 V, 12 V DC
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 STE9512D’s draw, cable, fuse, battery and run limit, as the maker publishes them.
Voltage Draw Maker’s cable Fuse Battery Run limit
12 V 650 Anominal draw 1/0 AWG for up to 8 ft of cable counted out and back. Longer runs take heavier cableinstallation manual 020584.05, r02, December 2024 425 Ainstallation manual 020584.05, r02, December 2024 1,083 CCA minimum, 2,166 CCA maximumVETUS installation manual 020584.05, r02, December 2024 3 min at a stretch, the manual's S2 ratinginstallation manual 020584.05, r02, December 2024

What holds up and what to weigh

Each point names the fact it rests on.

What holds up

  • VETUS sells it for either end, so it can go at the bow or the stern.The maker's listing

What to weigh

  • The boat comes out of the water to fit it: it needs a large hull opening below the waterline.The mounting: a bore through the hull, or a housing recessed into it
  • VETUS publishes no boat length for it. The boat table is our sizing alone.The maker's documents, as the database records them
  • No US dollar price is published for it, so we can work out no fitted cost.The maker and the dealers the database reads

What the manual and listings say

This is the note we keep on the VETUS STE9512D, 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.

Our note

A swing retractable. The unit lives in a housing with a seamless bottom plate and swings down when used. That makes a bigger yard job than a tunnel, and a mechanism to keep working. There is a 1.5 second delay between direction changes, and the unit retracts itself after 15 minutes unused. The biggest of the four, 12 V, in a 185 mm opening.

The manual gives 650 A, a battery of 1083 to 2166 cold cranking amps and a 425 A fuse. For cable it gives 1 AWG to 8.5 ft of total run (positive plus negative), and 4/0 to 20.7 ft. The motor is brushed, and its brushes and anode are checked yearly. No copper-based antifouling goes on the unit. We found no US dealer listing. VETUS publishes no price.

Videos

Two of VETUS’s own videos, from its YouTube channel: the retractable unit deploying and running, and how VETUS picks a size, a battery bank and a panel. 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

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.