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Thruster specs
Sleipner SAC700: specs, price and the boats it fits
The SAC700 is the only 412 mm unit in Sleipner’s AC line: 1543 lb of push for yachts of about 95 to 145 ft, from a three-phase motor and speed controller fed by the generator.
Imtra lists the 208 to 240 V build, mounted horizontal, at $40,700 before a separate tariff line. Its own manual gives 159 A at 230 V and 92 A at 400 V, a little above the figures in the SAC450 manual’s table. See the specs.
It is rated continuous at 700 kg, with a gravity-fed gear leg. The generator has to carry about 55 kVA when it runs. Warranty: two years.
Fitting it yourself? The installer section has every spec, and the Sleipner (Side-Power) review sets this model against the rest of the Sleipner range.
Where this summary comes from (5 sources, read 15 October 2026)
- Sleipner product page
- Sleipner SAC700 installation manual, document 6001 rev 17 (2026)
- Sleipner SAC450/SAC520 installation manual, document 5998 rev 15 (2025), with the table for every SAC model
- Imtra, Sleipner’s US distributor: SAC700 208 to 240 V listing (list price; tariff shown separately)
- Sleipner warranty statement, effective 1 April 2022
Key facts
- DIY level 2 of 5 Wiring prep only
- Thrust 1543 lb 700 kgf, Sleipner's rating
- Boat length 95 to 145 ft Sleipner's own range
- Price $40,700 equipment only, imtra.com, 15 October 2026
- Fitted by a yard $50,169 to $62,620 Our estimate at 120 ft, unit and job
- Voltage Not stated Ask the maker before wiring
- Mounts Tunnel Fixed mount, bow or stern
- 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 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 DIYYou: 4 to 16 h Yard: 32 to 70 h Electrician: 2 to 4 h Plus a haul-out.
- 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.
- 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.
- 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?
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. The maker gives one range for every boat.
The table below tries the Sleipner SAC700 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.
| Boat | Full thrust at 15 knots | Still 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 | No length. More thrust than the boat needs. | |
| Houseboat | No length. More thrust than the boat needs. | |
| Catamaran | No length. More thrust than the boat needs. | |
| Trawler | No length. More thrust than the boat needs. | |
| Motor yacht | No length. More thrust than the boat needs. | |
| 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 | No length. More thrust than the boat needs. | |
| 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.
No boat type and length in the table is a fit. 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 $1,740 to $7,000 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.
| Boat length | The unit | Yard labor | Haul-out | Batteries, cable, charger | Other parts | Total |
|---|---|---|---|---|---|---|
| 95 ft | $40,700 | $5,120 to $12,60032 to 70 hours | $1,740 to $4,580 | $1,000 to $1,400 | $1,189 to $2,130 | $49,749 to $61,410 |
| 120 ft | $40,700 | $5,120 to $12,60032 to 70 hours | $2,160 to $5,790 | $1,000 to $1,400 | $1,189 to $2,130 | $50,169 to $62,620 |
| 145 ft | $40,700 | $5,120 to $12,60032 to 70 hours | $2,580 to $7,000 | $1,000 to $1,400 | $1,189 to $2,130 | $50,589 to $63,830 |
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 Sleipner’s SE80 to SE150 installation guide, document 2687 rev 30, 2025, read 30 September 2026.
- In the box
- The gasket, bolts and anode come with the unit. The SEP guides call the power controller "the included PPC unit".
- Bought separately
- The ANL fuse and a main switch ("must include"), the control panel with its own guide, the panel cable, the tunnel and the cable.
- Charging
- The word "charging" is not in any of the Sleipner guides we read. The battery is sized by cold cranking amps, and a battery near the thruster is suggested. How it gets charged is left to you and your installer.
The manual’s words, page 19: “For installations on large vessels with bow and stern thrusters or catamarans a dedicated battery for each thruster should be considered.”
The “other parts” line in the estimate above is the priced parts below, $1,189 to $2,130 at Fisheries Supply’s prices on 30 September 2026. The batteries, cable and charger have a line of their own.
| 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. | Sleipner names none | $852–$1,315300 mm fiberglass tunnel tubes up to 60 in (1.5 m) long (Sleipner Side-Power), at Fisheries Supply, read 16 October 2026. No dealer we read lists a 412 mm tube. This is the 300 mm price, the largest bore listed. |
| Control panel | The buttons or joystick at the helm. One helm, one panel: a second steering station needs a panel of its own. | SM8960G single joystick, SM8950G touch panel | $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. | Side-Power 4-wire control 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. | Side-Power ANL fuse, 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. | SMANLHOLD (SMANLHOLD-C with a cover) | $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. | Side-Power manual main switch, 350 or 600 A, or the automatic AMS | $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. |
| Control-circuit fuse and switch | A small fuse, and often a switch, on the thin wire that powers the panel or control box. | Sleipner names none | $8–$12Blue Sea in-line ATO fuse holders, 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. | Sleipner 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. | Sleipner 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. | Sleipner 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. | Sleipner 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.
| Thrust and motor | |
|---|---|
| Thrust | 1543 lb (700 kgf) As printed: Thrust, continuous 700 kg |
| Motor | 42 kW |
| Voltage | Not stated |
| Fitting | |
| Type | Tunnel, fixed mount |
| End of the boat | Bow or stern |
| Tunnel diameter | 412 mm |
| What it does to the hull | Tunnel bore below the waterline |
| Haul-out to fit it | Yes |
| Maker’s boat length | 95 to 145 ft |
| The tunnel | |
| Tunnel length | Avoid a tunnel longer than four times its diameter. Friction inside a long tube slows the water and cuts thrust. Too short, and the flow reaches the propeller before it has straightened, which the manual says causes cavitation and noise. The propeller must sit entirely inside the tube. Sleipner’s installation manual |
| Depth below the waterline | As deep as possible under the waterline, and as far forward as possible. The depth for a given model is in that model’s own measurements. Deeper prevents air being sucked in from the surface and raises the water pressure at the propeller. SE20 to SE40 installation guide, 5611 rev 25 (2025) |
| Price and ordering | |
| Price | $40,700 equipment only, a dealer's price, imtra.com, 15 October 2026 |
| Part number | SAC700/412-C-2H208-240 V AC 3-phase |
| Documents | |
| Manual | Installation manualon the maker's product page |
| Warranty | Sleipner gives 2 years for leisure use and 1 for commercial use. It transfers to the next owner, and it starts no later than 18 months after the boat's first launch. Sleipner's warranty statement, effective 1 April 2022 |
| The site’s review | Sleipner (Side-Power) review |
What holds up and what to weigh
Each point names the fact it rests on.
What holds up
- Sleipner 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 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 Sleipner SAC700, written from the maker’s manual, its product pages and the dealer’s listing.
In the box: Gasket, bolts and anode with the unit. The panel, its cable, the fuse and main switch are bought.
Our note
It runs on three-phase AC from the boat's generator through a speed controller (VFD), not on a battery bank. This build is for 208 to 240 V, mounted horizontal.
Videos
Two of Sleipner’s own videos, from its YouTube channel: how the tunnel mouth changes the thrust you get, and the current E-series tunnel units. 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.
Other sizes and close alternatives
These are Sleipner’s next sizes in the same line, by thrust.
- One size down: Sleipner SAC520, 1146 lb, $30,300.
- One size up: Sleipner SAC900, 1984 lb, $49,230.
No other maker’s priced unit of this style sits within a quarter of its thrust. The compare page lists every model.
Every model with a page here is listed, maker by maker, on the thruster index.