Blue Sea Systems ST Blade Fuse Block 12 Circuits with Cover

The Blue Sea Systems ST Blade Fuse Block consolidates up to 12 branch circuits behind ATO/ATC blade fuses in one compact, screw-terminal block — a space-saving alternative to running individual in-line fuse holders or adding more breakers to a full panel.

Key features

• 12 circuits, 100A total, 30A per circuit, 32V DC maximum
• Positive distribution bus with #10-32 stud
• Tin-plated copper buses and fuse clips
• Clear insulating cover with push-button latch, spare-fuse storage, and label recesses satisfies ABYC/USCG requirements; includes 20 write-on circuit labels
• Accepts ring or snap-fork terminals; can be used for 24-hour circuits

A single circuit breaker on the main distribution panel can feed this block, which then consolidates fusing for several downstream electronics or accessories that each have their own on/off switch and don't need a dedicated panel breaker. It's a common pattern for adding electronics — a stereo, a chartplotter, a bilge pump — without running out of panel positions.

Torque the screw terminals to 18 in-lb and the bus stud connections to 24 in-lb. Choose the negative-bus version if you want circuit grounds consolidated at the block itself; choose the non-negative-bus version if grounds are already handled at a separate bus bar elsewhere in the boat. This 12-circuit size is a common choice when consolidating a bank of small electronics — instruments, pumps, lighting circuits — that would otherwise eat up a dozen positions on the main panel. Torque the bus stud connections to 24 in-lb before energizing the circuit, and double check each branch fuse is rated below the wire gauge feeding it.