Overview

The Blue Sea Systems 7900 is a red spare key for the M-Series Mini On-Off Battery Switch, part 6005. It is a straightforward replacement item for boats that use this keyed battery switch and need a backup on hand in case the original key is lost, damaged, or kept with another set of onboard keys.

This is the key only, not a complete switch. For owners who lock or remove the key when the boat is unattended, a spare can be worth keeping near the electrical panel, in the ship's papers, or with the service kit so the battery can still be isolated before storage, transport, or maintenance.

Key features

• Fits the Blue Sea Systems M-Series Mini On-Off Battery Switch, part 6005
• Red replacement key for the keyed M-Series mini switch application
• Useful as a backup when the original key is misplaced or when more than one trusted user needs access to the battery switch
• Sold as the spare key only, so it works as a replacement part rather than a full switch assembly

Compatibility and fit

Fit is the main buying check for this part. It matches the keyed M-Series mini battery switch identified as 6005, so it is best used when you are replacing a missing key for that switch or keeping a second key with the same setup. If your boat uses a different Blue Sea switch family or a different key style, this part should be matched carefully before ordering.

Use on board

This spare key makes sense for trailer boats, small cruisers, sailboats, and workboats that use the 6005 switch to disconnect battery power when leaving the dock or carrying out electrical work. It is also a sensible item for owners who hand the boat off between family members, crew, yard staff, or service technicians and want a second key available without removing the switch from service.