Six Models. Every Engine Size. One Solution.
From a single-engine center console to a twin-engine offshore sportfisher, there’s a BoatStartPlus™ built for your vessel. Our proprietary supercapacitor technology installs permanently alongside your existing battery and delivers instant, reliable starting power — on engines from under 7 liters all the way up to 32 liters. One installation. Zero maintenance. A boat that starts every time.
BoatStartPlus™
SKU: MKSM2012
The Original. Perfect for smaller outboards and single-engine boats.
| wdt_ID | wdt_created_by | wdt_created_at | wdt_last_edited_by | wdt_last_edited_at | SPECS | VALUE |
|---|---|---|---|---|---|---|
| 2 | Voltage | 12V | ||||
| 3 | Cells | 20-cell | ||||
| 4 | Capacitance | 240F | ||||
| 5 | Max Power | 42.05 kW | ||||
| 6 | Engine Size | Up to 7L | ||||
| 7 | Internal Resistance | |||||
| 8 | Energy Stored | |||||
| 9 | Dimensions | 14.25" x 10.25" x 6.25" | ||||
| 10 | Weight | 8 lbs | ||||
| 11 | Operating Temp | -40°F to 149°F | ||||
| 12 | Warranty | 3 yr module / 1 yr components | ||||
| 13 | Price List |
BoatStartPlus™ XL
SKU: MKSM612
More capacity for bigger single-engine vessels.
| wdt_ID | wdt_created_by | wdt_created_at | wdt_last_edited_by | wdt_last_edited_at | SPECS | VALUE |
|---|---|---|---|---|---|---|
| 2 | Voltage | 12V | ||||
| 3 | Cells | 6-cell | ||||
| 4 | Capacitance | 525F | ||||
| 5 | Max Power | 47 kW | ||||
| 6 | Engine Size | Up to 8L | ||||
| 7 | Internal Resistance | 0.0011 ohms | ||||
| 8 | Energy Stored | 42.3 kJ | ||||
| 9 | Dimensions | 14.79" x 7.75" x 8" | ||||
| 10 | Weight | 22 lbs | ||||
| 11 | Operating Temp | -40°F to 149°F | ||||
| 12 | Warranty | 3 yr module / 1 yr components | ||||
| 13 | List Price | $2,899.98 |
Step up to the XL when your engine demands more. With 525 farads of capacitance and 47 kW of starting power, the XL handles engines up to 8 liters with ease — and still delivers a reliable start even when your battery is completely depleted.
BoatStartPlus™ Boost
SKU: MKSM1012
Built for twin-engine vessels and larger offshore boats.
| wdt_ID | wdt_created_by | wdt_created_at | wdt_last_edited_by | wdt_last_edited_at | SPECS | VALUE |
|---|---|---|---|---|---|---|
| 2 | Voltage | 12V | ||||
| 3 | Cells | 10-cell | ||||
| 4 | Capacitance | 1,260F | ||||
| 5 | Max Power | 112 kW | ||||
| 6 | Engine Size | Up to 15L | ||||
| 7 | Internal Resistance | 0.0008 ohms | ||||
| 8 | Energy Stored | 101.6 kJ | ||||
| 9 | Dimensions | 19.44" x 7.75" x 8" | ||||
| 10 | Weight | 32 lbs | ||||
| 11 | Operating Temp | -40°F to 149°F | ||||
| 12 | Warranty | 3 yr module / 1 yr components | ||||
| 13 | List Price | $3,866.64 |
The Boost is our most popular choice for serious offshore anglers and twin-engine sportfishers. With 1,260 farads and 112 kW of starting power, it handles demanding engine configurations up to 15 liters — and gives you the confidence to head out knowing your boat will start, every single time.
BoatStartPlus™ Turbo
SKU: MKSM1212
Maximum 12V power for the most demanding twin-engine setups.
| wdt_ID | wdt_created_by | wdt_created_at | wdt_last_edited_by | wdt_last_edited_at | SPECS | VALUE |
|---|---|---|---|---|---|---|
| 2 | Voltage | 12V | ||||
| 3 | Cells | 12-cell | ||||
| 4 | Capacitance | |||||
| 5 | Max Power | |||||
| 6 | Engine Size | Up to 15L | ||||
| 7 | Internal Resistance | |||||
| 8 | Energy Stored | |||||
| 9 | Dimensions | |||||
| 10 | Weight | |||||
| 11 | Operating Temp | -40°F to 149°F | ||||
| 12 | Warranty | 3 yr module / 1 yr components | ||||
| 13 | List Price | $4,115.80 |
BoatStartPlus™ Ultra
SKU: MKSM1024
The 24V solution for larger vessels and serious offshore powerboats.
| wdt_ID | wdt_created_by | wdt_created_at | wdt_last_edited_by | wdt_last_edited_at | SPECS | VALUE |
|---|---|---|---|---|---|---|
| 2 | Voltage | 24V | ||||
| 3 | Cells | 10-cell | ||||
| 4 | Capacitance | 315F | ||||
| 5 | Max Power | 112 kW | ||||
| 6 | Engine Size | Up to 32L | ||||
| 7 | Internal Resistance | 0.0019 ohms | ||||
| 8 | Energy Stored | 112.4 kJ | ||||
| 9 | Dimensions | 19.44" x 7.75" x 8" | ||||
| 10 | Weight | 32.5 lbs | ||||
| 11 | Operating Temp | -40°F to 149°F | ||||
| 12 | Warranty | 3 yr module / 1 yr components | ||||
| 13 | List Price | $3,866.64 |
Running a 24V electrical system? The Ultra is your answer. Built for larger offshore powerboats and multi-engine vessels with engines up to 32 liters, it delivers 112 kW of starting power and the same bulletproof reliability as every BoatStartPlus™ model — in any weather, at any temperature.
BoatStartPlus™ Max
SKU: MKSM1224
The ultimate BoatStartPlus™ for the largest, most demanding vessels.
| wdt_ID | wdt_created_by | wdt_created_at | wdt_last_edited_by | wdt_last_edited_at | SPECS | VALUE |
|---|---|---|---|---|---|---|
| 2 | Voltage | 24V | ||||
| 3 | Cells | 12-cell | ||||
| 4 | Capacitance | 263F | ||||
| 5 | Max Power | 94 kW | ||||
| 6 | Engine Size | Up to 32L | ||||
| 7 | Internal Resistance | 0.0022 ohms | ||||
| 8 | Energy Stored | 102 kJ | ||||
| 9 | Dimensions | 19.44" x 7.75" x 8" | ||||
| 10 | Weight | 34.5 lbs | ||||
| 11 | Operating Temp | -40°F to 149°F | ||||
| 12 | Warranty | 3 yr module / 1 yr components | ||||
| 13 | List Price | $4,115.80 |
The MAX is the pinnacle of the BoatStartPlus™ family. Engineered for the largest 24V vessels — from big express cruisers to heavy offshore sportfishers — the MAX delivers up to 32 liters of engine compatibility with 12-cell construction and 94 kW of reliable starting power. When everything is on the line, the MAX delivers.
Compare All Six Models
Not sure which model is right for your boat? Use this table to match your engine size and electrical system.
| BoatStartPlus™ | BoatStartPlus™ | BoatStartPlus™ Boost | BoatStartPlus™ Turbo | BoatStartPlus™ Ultra | BoatStartPlus™ Max | |
| SKU | MKSM2012 | MSKM612 | MKSM1012 | MKSM1212 | MKSM1024 | MSKM1224 |
| Voltage | 12V | 12V | 12V | 12V | 24V | 24V |
| Cells | 20 | 6 | 10 | 12 | 10 | 12 |
| Capacitance | 240F | 525F | 1,260F | 315F | 315F | |
| Max Power | 42.05 kW | 47 kW | 112 kW | 112 kW | 94 kW | |
| Engine Size | Up to 7L | Up to 8L | Up to 8L | Up to 15L | Up to 23L | Up to 23L |
| Weight | 8 lbs | 22 lbs | 32 lbs | 32.5 lbs | 34.5 lbs | |
| Start Cycles | 1,000,000 | 1,000,000 | 1,000,000 | 1,000,000 | 1,000,000 | 1,000,000 |
| Price | $2,899.98 | $3,866.64 | $4,115.80 | $3,866.64 | $4,115.80 |
Not sure which model fits your engine?
Call (800)527-8278 and we’ll match you to the right BoatStartPlus™ for your vessel.
Built for Operators Who Can’t Afford a No-Start
“The value the KSM has provided is me knowing that my boat will start every time. It’s peace of mind when I’m 30-40 miles offshore. I don’t want my starting bank to drain and be stuck out there. Knowing that capacitor is holding the charge and can start the motor is what sold me.”
– Captain Mike Littlefield, Archangel Fishing Charters
Engineering You Can Count On
Instant Power
Maximum cranking amps released in milliseconds—no chemical delay
30-Second Recharge
Fully recharged in 30 seconds from any 12V source
All Temps
Full power from -40°F to 149°F with zero degradation
No Charging
Supercapacitor technology—never needs charging, no batteries to replace
Waterproof
IP67 rated components stand up to saltwater, extreme weather, and combat conditions
Made in USA
Designed and manufactured in Lake in the Hills, Illinois
Your Boat Should Start Every Time. Make It Happen.
BoatStartPlus™ is the last starting upgrade you’ll ever need. Choose the model that fits your vessel, install it once, and forget about dead batteries forever.
Questions? Call (800)527-8278 — we’ll help you choose the right model for your boat.