
Blue Sea Systems Lockout Slide, 2 Position, 2 Pole
Mechanical interlock for 2 double-pole AC source breakers
SKU BLUE-4125B
Lockout Slide, 2 position, 2 pole, for AC double-pole circuit breakers. Prevents mixing multiple AC power sources. Mounting screws included.
- Positions
- 2
- Poles
- 2
- Compatible Breakers
- World/A-Series and Rocker double-pole
- Weight
- 0.02 lb
- Manufacturer
- Blue Sea Systems
Stocked items typically ship the next business day from our US warehouse. 30-day returns on unused stocked items. Exclusions apply. Return policy · Shipping policy
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About this product
Blue Sea Systems Lockout Slide, 2 position, 2 pole, prevents mixing multiple AC sources. Manufacturer PN 4125.
The Blue Sea Systems Lockout Slide is a simple mechanical interlock that allows only one of 2 double-pole AC circuit breakers to be switched on at a time — guaranteeing that power from shore, a generator, and an inverter can never accidentally be connected together.
Key features
- 2 position, 2 pole design
- Allows only 1 double-pole AC circuit breaker to be activated at a time
- Fits all World/A-Series and Rocker double-pole circuit breakers
- Uses existing circuit breaker mounting screw holes — no panel modification required
- Includes mounting screws
This is a genuinely important safety feature on any boat with more than one AC power source. Connecting shore power and a generator (or an inverter) to the same AC bus at the same time can backfeed power into a source that isn't expecting it, creating a real shock and fire hazard, and potentially damaging equipment on both ends. This slide makes that mistake mechanically impossible rather than relying on the operator to remember not to do it.
Because it uses the breaker's existing mounting screws rather than requiring any panel modification, this is a straightforward retrofit onto an existing panel with two or three double-pole AC source breakers already installed side by side.
This kind of interlock is worth adding to any panel where shore power, a generator, and an inverter all terminate on separate double-pole breakers, since it's the kind of mistake that's easy to make once — plugging into shore power while the generator breaker is still on, for example — but this slide simply removes that possibility from the equation entirely.
Product details
- Positions
- 2
- Poles
- 2
- Compatible Breakers
- World/A-Series and Rocker double-pole
- Weight
- 0.02 lb
- Manufacturer
- Blue Sea Systems
Shipping & returns
- Stocked items typically ship the next business day from our US warehouse.
- 30-day returns on unused stocked items. Exclusions apply. See policy
- Custom and quoted items are non-returnable once production begins.
Warranty
Backed by the original manufacturer’s warranty plus our workmanship guarantee on assembled harnesses. Contact us with your invoice and we’ll coordinate any covered repair or replacement.
Read the full warranty termsTechnical support
Need help choosing the right part?
Our marine electrical team can review your setup and recommend compatible products. Send a photo, a sketch, or your circuit list and we'll come back with a parts list that fits the boat.
Certifications & training
- ABYC-aware build practices
- OEM-grade marine wire & terminals
Additional capabilities are based on hands-on experience building marine wiring systems rather than third-party certification.
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Why buy from Common Ground Marine
- 20+ years building marine wiring harnesses, panels, and shore-power systems.
- Engineers — not a phone tree — review every custom build before parts are cut.
- OEM-grade components: tinned copper, sealed connectors, marine-rated jackets.
