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Sleipner · external thruster · stern
Sleipner SX100: specs, price and the boats it fits
It gives 256 lb (116 kgf) of push. Sleipner sells it for boats of 39 to 56 ft. It runs on 12 V or 24 V.
- Haul-out to install
- DIY 3 of 5: split with the yard
- 2-year warranty
Quick stats
- Thrust 256 lb 116 kgf, Sleipner's rating
- Boat length 39 to 56 ft Sleipner's own range
- Price per lb of thrust $38.09 Unit only. $52 to $70 installed
- Voltage 12 V or 24 V As sold
- Battery at 12 V 713 CCA Two batteries, near the thruster
- Run limit Not published Ask the maker before long use
- To install it Haul-out The boat comes out of the water
- Anodes $28.80 A change, at Defender
About the Sleipner SX100
The SX100 is the larger SX stern unit, for boats of about 39 to 56 ft with twin stern drives: 256 lb of push from a sealed unit bolted to the outside of the transom. Its cowls send the water past the drives, and it needs only a small hole for its cables.
Imtra lists it at $9,750 at 12 or 24 V, before a separate tariff line. Add about $307 to $642 for the control panel, fuse and main switch, and $961 to $1,180 for a stern battery, cable and charger. The parts list.
Read more
It is on/off, rated for 2 to 3 minutes of running at a time. At 12 V it draws about 740 A, so a 24 V bank and a battery close to the stern keep the cable sensible. Its warranty runs two years and stays with the boat when it is sold.
Installers will find the wiring figures and dimensions further down. For the rest of Sleipner’s line, read the Sleipner (Side-Power) review.
Sleipner sold its thrusters under the Side-Power name until 2021, and many dealers and owners still call them that. It is the same company and the same thrusters.
Where this summary comes from (4 sources, read 14 October 2026)
Will the Sleipner SX100 steer your boat?
61 FT TRAWLER · STERN · 15 KT WIND
Every knot figure here is wind speed, not boat speed or current.
On a 61 ft trawler the Sleipner SX100 (256 lb) steers her in a 19 knot breeze. Her stern needs about 173 lb from an external unit on the transom to steer her in a 15 knot breeze.
The finder lists it for her.
The Sleipner SX100 on a trawler, by length
- 25 ft45 kt
- 30 ft38 kt
- 35 ft32 kt
- 40 ft28 kt
- 45 ft25 kt
- 50 ft23 kt
- 55 ft21 kt
- 60 ft19 kt
- 65 ft18 kt
- 70 ft16 kt
- 75 ft15 kt
- 80 ft14 kt
Outlined: the finder does not list it at that length (under 13 kt, far more than she needs, or outside Sleipner’s own length range).
- Under 10 kt
- 10 to 15 kt
- 15 to 20 kt: the sweet spot
- Over 20 kt: more than she needs
Prices are the low end of the installed total, from our estimate. For your own boat, drive and installer, the finder prices each unit.
Is it right for your boat?
Every kind of boat it fits, by length
| Boat | Full thrust at 15 knots | Still a fit, in lighter wind |
|---|---|---|
| Pontoon & tritoon | Not listed. Its maker does not name this kind of hull. | |
| Sailboat | 53 to 61 ft | None |
| Houseboat | Not listed. Its maker does not name this kind of hull. | |
| Catamaran | Not listed. An external unit bolts to the side of a single hull at the bow or to its transom, and a cat has two narrow hulls with a bridgedeck between them, so there is nowhere forward to hang one. | |
| Trawler | 53 to 61 ft | None |
| Motor yacht | 53 to 61 ft | None |
| Bass & flats | Not listed. This site does not list it for this kind of boat. | |
| Wake & ski boats | Not listed. This site does not list it for this kind of boat. | |
| Express cruiser | No length. More thrust than the boat needs. | |
| Center console | Not listed. This site does not list it for this kind of boat. | |
The Sleipner SX100 against each kind of boat, in a 15 knot wind. Our sizing, from the finder’s own rules.
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 steers her in a 13 or 14 knot wind, within 15 percent of the 15 knot breeze this site sizes for. On a boat shorter than the first column’s shortest length, the unit is more than the boat needs.
How we size it
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 every kind of boat it fits gets full thrust to 61 ft. The maker gives one range for every boat.
The table tries the Sleipner SX100 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 where it mounts 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 61 ft, just past Sleipner’s own range (39 to 56 ft).
It is sized for three kinds of boat here. For your own boat, the finder gives an answer that also counts your drive and who does the installing. The compare page sets this unit beside others.
What it costs installed
A yard job, everything in. Our estimate.
| Boat | Total installed |
|---|---|
| 53 ft | $13,338 to $17,732$52 to $69 a lb of thrust |
| 55 ft | $13,378 to $17,822$52 to $70 a lb of thrust |
| 61 ft | $13,478 to $18,112$53 to $71 a lb of thrust |
From the shortest to the longest boat it is sized for.
What is in each total
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 $1,040 to $2,940 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. The cost page builds the same figures line by line.
| Boat length | The unit | Yard labor | Haul-out | Batteries, cable, charger | Other parts |
|---|---|---|---|---|---|
| 53 ft | $9,750 | $1,280 to $3,6008 to 20 hours | $1,040 to $2,560 | $961 to $1,180 | $307 to $642 |
| 55 ft | $9,750 | $1,280 to $3,6008 to 20 hours | $1,080 to $2,650 | $961 to $1,180 | $307 to $642 |
| 61 ft | $9,750 | $1,280 to $3,6008 to 20 hours | $1,180 to $2,940 | $961 to $1,180 | $307 to $642 |
For every length in the table above.
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 26 October 2026.
- At 12 V: two 12 V batteries side by side (in parallel), at least 713 CCA each (Sleipner’s minimum), $720 for both; Sleipner’s cable table gives 3/0 AWG, priced on 4/0 AWG, the nearest size cut to length: $180 to $314 for the red and black cable and the lugs; a GEN5X2 charger, $146.
- At 24 V: two 12 V batteries in series, at least 760 CCA each (Sleipner’s minimum), $720 for both; Sleipner’s cable table gives 1/0 AWG: $95 to $171 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.
DIY breakdown
DIY levels
- Level 5: Owner install. No yard, no electrician.
- Level 4: You install 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 installs 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 hours Yard: 4 to 8 hours Electrician: 2 to 4 hours Plus a haul-out.
Your part needs:Heavy battery cableCrimping big lugs
Every step, and who does it
- Drill, seal and bolt the unit below the waterline Yard 4 to 8 hours Our estimate. No maker times it; one owner paid his yard about a day of labor to mount two units. Source.
- Mount the battery box, switch and fuse holder; run and secure the cables You 4 to 16 hours 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 hours Our estimate. Nobody publishes a time for the final connections and test on their own.
A qualified marine electrician should make the final connections and test them before first use. Hours are labor only.
Related videos
One from Sleipner’s own channel and two from other channels. Each one is labeled. They play from YouTube only when you tap. Take any claim in a video back to the figures on this page, which are the ones we checked.
Know before you buy
What sets this model apart, what it costs to keep, and what to weigh.
Price per pound of thrust
$38.09 a lb The unit’s price over its published thrust. The bars are Sleipner’s next sizes and the nearest other makers.Controls
Gasket, bolts and anode with the unit. The panel, its cable, the fuse and main switch are bought.
- On/off control panel (4-wire), no US price found.
- Side-Power 4-lead control cable, 4 m (SM61277-04M), $29.23 at Fisheries Supply.
Anodes
$28.80 a change- Anode (SM71190A): $14.40 at Defender, $18.01 at Fisheries Supply, and it takes two.
Service and 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.
See Sleipner’s warranty Sleipner's warranty statement, effective 1 April 2022.Special mentions
Battery: at 12 V it wants two batteries of 713 CCA or more, Sleipner's figure. The cheapest that meets it is the Optima BlueTop SC27DM Group 27 AGM, $359.99. Check your own bank.
Charger: a NOCO GEN5X2 two-bank shore charger, $146.41. It is the one our estimate prices.
Dealer prices at Fisheries Supply, read 26 October 2026.What to weigh
The boat comes out of the water to install it: it needs a small hole in the transom for the power and control cables.
At 12 V it draws 740 A, so the battery cable is heavy and the battery sits close to it.
Parts for the Sleipner SX100
See the Sleipner SX100 manualThe US dealer number comes first, then Sleipner’s own. Prices are each dealer’s on the day shown, before shipping and tax. Check the plate on your motor before you order: some parts change with the tunnel size, the voltage or the year.
For the install what the box leaves you to buy
The manual button above opens it on the maker's product page. It has the hull, wiring and fuse figures for this model.
From Sleipner’s SX80 and SX100 installation manual, document 2879 rev 7, 2025, read 16 October 2026.
- In the box
- The unit comes assembled, wired and sealed. The manual mentions the bolts for the grids or cowls, and a drilling template where one is included.
- Bought separately
- The battery, the ANL fuse, a main switch (manual or Sleipner's automatic one), the battery cable, the control panel and its control 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.
In Sleipner’s words, from its SE80 to SE150 installation guide, document 2687 rev 30, 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 covers these parts as a range, $307 to $642 at Fisheries Supply’s prices on 30 September 2026 and 26 October 2026, because the exact items depend on your boat. The batteries, cable and charger have a line of their own. The cost page has what every maker says about each part.
Control panel
Ask for On/off control panel (4-wire).
No part number is printed for it. A Sleipner dealer can give you the one that suits this model.
Control cable, panel to thruster
Fisheries Supply lists it as “Side-Power 4-lead control cable, 4 m”.
Sold in lengths from 4 to 22 m. This is the shortest: measure the run from the helm to the thruster and buy the length that reaches.
Main fuse
Fisheries Supply lists it as “Side-Power ANL fuse 500 A”. This one is for the 12 V version.
The maker's figure: ANL 500.
Main fuse
Fisheries Supply lists it as “Side-Power ANL fuse 325 A”. This one is for the 24 V version.
The maker's figure: ANL 325.
Fuse holder
Fisheries Supply lists it as “ANL fuse block, 35 to 750 A, cable up to 4/0, with cover”.
Battery switch
Fisheries Supply lists it as “HD-Series 600 A battery switch, on/off”. This one is for the 12 V version.
Rated at or above the 500 A main fuse. If your manual names its own switch, use that one.
Battery switch
Fisheries Supply lists it as “e-Series 350 A battery switch, on/off”. This one is for the 24 V version.
Rated at or above the 325 A main fuse. If your manual names its own switch, use that one.
Control-circuit fuse holder
Fisheries Supply lists it as “Waterproof in-line ATO/ATC fuse holder”.
Your manual names no value for this: size a small in-line fuse to the wire.
Batteries
Fisheries Supply lists it as “Optima BlueTop SC27DM Group 27 AGM”. This one is for the 12 V version.
You need 2, each at 713 CCA or more, in parallel. The cheapest listing that meets it.
Batteries
Fisheries Supply lists it as “Optima BlueTop SC27DM Group 27 AGM”. This one is for the 24 V version.
You need 2, each at 760 CCA or more, in series for 24 V. The cheapest listing that meets it.
Battery cable, red and black
Defender lists it as “Ancor tinned battery cable 4/0 AWG, cut to length, red or black”. This one is for the 12 V version.
You need 10 ft of each color. For about 20 ft of cable in all, out and back. Measure your run and check it against the cable table in the manual: never go smaller than it asks for.
Battery cable, red and black
Defender lists it as “Ancor tinned battery cable 1/0 AWG, cut to length, red or black”. This one is for the 24 V version.
You need 10 ft of each color. For about 20 ft of cable in all, out and back. Measure your run and check it against the cable table in the manual: never go smaller than it asks for.
Cable lugs
Fisheries Supply lists it as “Tin-plated starter lugs, 4/0 AWG, bag of 10”. This one is for the 12 V version.
The listing runs $47.52 to $49.44 by stud size. Eight ends on one run, with two spare.
Cable lugs
Fisheries Supply lists it as “Tin-plated starter lugs, 1/0 AWG, bag of 10”. This one is for the 24 V version.
The listing runs $23.74 to $28.04 by stud size. Eight ends on one run, with two spare.
Charger
Fisheries Supply lists it as “GEN5X2 on-board charger, 10 A, 2 banks”.
Or a DC-to-DC charger from the house system: ask the electrician.
Outside the hull replacement parts in the water
Anode (takes two)
The metal that wears away in the water so the drive does not. Sleipner calls it “Anode, aluminium SE60/80/100”.
Propeller (takes two)
The propeller on the drive. Sleipner calls it “Propeller SE80/100 5bl Q-Prop™”.
Two per thruster. Sleipner lists it in gear leg 8 0601, which its gear leg page lists for every SX80, SX100, SXP80 and SXP100.
Drive pin (the pin that drives the propeller)
The pin that locks the propeller to its shaft. Sleipner calls it “Drive pin propeller SE60/80/100 (4/6/7HP)”.
Upper cover O-ring
It keeps water out of the joint it sits in. Sleipner calls it “O-ring Ø8x473mm”.
Part of cover kit SM168434.
Flexible coupling (joins motor and gear leg)
The leg under the motor that turns the propeller. Sleipner calls it “Flexible coupling Ø20-Ø16”.
Inside the sealed unit on the transom, outside the hull.
Gear leg gasket
The leg under the motor that turns the propeller. Sleipner calls it “Gasket kit for gearleg/tunnel”.
Gear leg without propellers
The leg under the motor that turns the propeller. Sleipner calls it “Gearleg SE80/100 w/out propeller”.
Sleipner lists it in gear leg 8 0601, which its gear leg page lists for every SX80, SX100, SXP80 and SXP100.
Gear leg, complete
The leg under the motor that turns the propeller. Sleipner calls it “Gearleg SE80/100”.
Sleipner describes it as the complete gearbox.
Upper cover kit
Sleipner calls it “Cover chassis, upper part kit SX80/100”.
Includes O-ring 74321 A. The SXP100 12V is on its own model page, not on this part page.
Moisture absorbing pack
Sleipner calls it “Moisture absorbing pack”.
Inside the sealed unit on the transom, outside the hull.
Replacement motor
The electric motor that turns the propeller. Sleipner calls it “Electric motor”. It fits the 12V size on this page.
Inside the sealed unit on the transom, outside the hull.
Replacement motor
The electric motor that turns the propeller. Sleipner calls it “Electric motor 24V”. It fits the 24V size on this page.
Inside the sealed unit on the transom, outside the hull.
Inside the boat replacement parts on board
Main fuse
The main fuse at the battery, in the rating the maker gives. Sleipner calls it “Recommended fuse A”. It fits the 12V size on this page.
The rating on Sleipner’s page for this model.
Main fuse
The main fuse at the battery, in the rating the maker gives. Sleipner calls it “Recommended fuse A”. It fits the 24V size on this page.
The rating on Sleipner’s page for this model.
No part matches. Try the number without spaces, or the part’s name.
The install parts are matched to Sleipner’s own figures and priced at Fisheries Supply, with the battery cable at Defender, cut to length.
Spare part numbers come from Sleipner’s parts pages and manuals. A dealer may sell a part we have not priced. Search for the number.
Other sizes and close alternatives
- Size down Sleipner SX80 212 lb · $8,750
- Size up Sleipner EX180D 287 lb · $17,750
- Same thrust Sleipner SXP100 PRO 256 lb · $12,500
- Other maker Max Power CT125 stern pod 254 lb · $4,913
The other makers listed are the nearest match each makes, of the same style and for the same end, within a quarter of its thrust. The compare page lists every model, and the thruster index lists every model with a page here.
For the yard and the installer
Every published figure, with its source.
Full spec sheet
| Thrust and motor | |
|---|---|
| Thrust | 256 lb (116 kgf) As printed: "SX(P)100 12V 12V 116 kg (12V) 100 kg (10.5V)" - Sleipner SX80/SX100 installation manual, document 2879 rev 7 (2025), Product Specifications MC_0415 |
| Thrust under load | 220 lb at 10.5 V |
| Motor | 6.3 kW |
| Voltage | 12 V or 24 V |
| Run limit | Not published |
| Installation | |
| Type | External, fixed mount |
| End of the boat | Stern |
| Tunnel diameter | 185 mm |
| What it does to the hull | A small hole in the transom for the power and control cables |
| Haul-out to install it | Yes |
| Maker’s boat length | 39 to 56 ft |
| Price and ordering | |
| Price | $9,750 full kit, a dealer's price, imtra.com, 26 October 2026 |
| Part number | SX100/185T-12V12 V, 12 V DC (nominal 10.5 V DC) SX100/185T-24V24 V, 24 V DC (nominal 21 V DC) |
| Documents | |
| Manual | Installation manualon the maker's product page |
| The site’s review | Sleipner (Side-Power) review |
Every published figure the site holds for the Sleipner SX100, with where each came from.
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.
| Voltage | Draw | Maker’s cable | Fuse | Battery | Run limit |
|---|---|---|---|---|---|
| 12 V | 740 Anominal draw | 3/0 AWG for up to 22 ft of cable counted out and back. Longer runs take heavier cableinstallation guide | ANL 500installation guide | 750 CCA DIN minimumSleipner installation guide, SX80 and SX100 external, document 2879 rev 7 (2025) | Not published |
| 24 V | 340 Anominal draw | 1/0 AWG for up to 22 ft of cable counted out and back. Longer runs take heavier cableinstallation guide | ANL 325installation guide | 400 CCA DIN minimumSleipner installation guide, SX80 and SX100 external, document 2879 rev 7 (2025) | Not published |
The Sleipner SX100’s draw, cable, fuse, battery and run limit, as the maker publishes them.
- At 12 V: size the cable for your run, or check the battery you have.
- At 24 V: size the cable for your run, or check the battery you have.
Our notes from the manual and listings
In the box: Gasket, bolts and anode with the unit. The panel, its cable, the fuse and main switch are bought.
12 V
A stern thruster for boats with twin stern drives: a sealed unit bolted to the outside of the transom, delivered assembled and wired, that needs only a small hole in the transom for its cables. Cowls redirect its flow past the drives. On/off.
Where each point above comes from
- It is sold at 12 V and at 24 V.The maker's and dealers' listings
- Sleipner also prints a second, lower thrust figure for when the battery sags under load: 220 lb at 10.5 V.The maker's published rating
- The boat comes out of the water to install it: it needs a small hole in the transom for the power and control cables.The mounting style
Not sure this is the one? The thruster finder asks about your boat and prices every unit that fits.