Blue Sea Systems 12 Circuit ST Blade Fuse Block with Negative Bus Use the Blue Sea Systems ST Blade Fuse Block to consolidate branch circuits and in-line fuses. Blue Seas ST Blade Fuse Block offers a space saving and cost effective solution to adding circuit protection when there are limited available circuit breakers on the distribution panel. Features Can be used for 24 hour circuits Includes ABYCUSCG approved cover with an easy to open push button latch Include 20 write-on circuit labels Tin-