Seakeeper 40

The Seakeeper 40 is designed to eliminate up to 95% of
boat roll on boats 85 feet and up (up to 115 tons) and
now features field replaceable bearings (FRB). Engineered
from the previous Seakeeper 35 model, we've improved
performance without sacrificing power, space, or weight.
Multiple units can be fitted for larger boats.

$337,800 (not including installation)
Seakeeper 40

Ideal for Boats


~ 23' - 30'

~ 30' - 36'

3Asset 1

~ 35' - 41'

~ 38' - 44'

~ 40' - 46'

~ 44' - 53'

~ 50' - 60'

~ 50' - 62'

~ 55' - 68'

~ 60' - 75'

~ 70' - 85'

~ 85' - 110'

Seakeeper 40 shown to scale here on a Dominator 29M Avantgarde.

Completely Internal Stabilization

Small & Lightweight

Seakeeper weighs only a small fraction of the boat's displacement

Eliminate Boat Roll

Eliminate up to 95% of boat roll and the danger, fatigue, anxiety, and seasickness that go with it

Flexible & Efficient

Unlike traditional fins, Seakeeper is completely internal and can be installed virtually anywhere

Take a Look Under the Hood

Weight 4,074 lbs (1,848 kg)
Dimensions 54.3 L x 55.9 W x 40.6 H (inches)
1.38 L x 1.42 W x 1.04 H (meters)
View full spec sheet Seakeeper 40

Innovative Cooling System

Our patented cooling system allows the flywheel to spin at an extremely high rate of speed, providing ultimate performance in the smallest and lightest package possible.

Vacuum Sealed

Seakeeper’s vacuum encapsulation enables the flywheel to spin roughly three times faster, cuts flywheel weight by two-thirds and halves power requirements. Moreover, because the critical components (flywheel, bearings, and motor) are sealed in a vacuum, they are isolated from the marine environment.

Active Control

Seakeeper’s active control optimizes gyro torque, providing an unsurpassed level of performance. Unlike a passively controlled gyro, which must be turned off in the roughest conditions and/or at higher speeds, the Seakeeper is effective at all speeds and can be used in all sea conditions.

Intuitive Dash Display

Control your Seakeeper with the push of a button on our new user-friendly dash display. Not only is the display simple to use, but it integrates into your existing dash units for optimal performance.

Seakeeper 40


Max Rated Speed 5,150 RPM
Angular Momentum at Max Rated RPM 40,000 N-M-S
Anti-Rolling Torque at Max Rated RPM 104,720 N-M
Spool-up Time to Max Rated RPM 70 minutes (5,150 RPM)
Spool-up Time to Stabilization 40 minutes (3,863 RPM)
Spool-up Power
Spool-Up Power 5000 Watts
Operating Power 1,900 - 4,400 Watts
Operating Power Input 208-230 VAC @ 30 Amps, 50/60 Hz
Control Power 240 Watts Max
Control Power Input 24 VDC @ 15 Amps Max
Seawater Pump Power Input 24 VDC @ 20 Amps Max
Sea Water Supply to Heat Exchanger 13 GPM (49 LPM) Minimum 15 GPM (57 LPM) Maximum
Weight 4,074 lb (1,848 kg)
Envelope Dimensions 54.3 L x 55.9 W x 40.6 H (inches) 1.38 L x 1.42 W x 1.04 H (meters)
Noise Output <73 dBC @ 3.3 feet (1 meter)
Ambient Air Temperature 32F - 140F (0C - 60C)

Seakeeper Warranty

To ensure peace of mind, all Seakeeper products come
with a multi-year factory warranty

View Warranty Details

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