This modular design negative bus bar and blade fuse holder series is ideal for marine and auto applications. These two models can be combined to make four popular fuse blocks depending on requirements. Each fuse block enables 6 fused circuits; mount two units neatly together to enable 12 fused circuits, in addition you can mount the 12P negative bus bar to either option just mentioned or use it alone as required. These fuse blocks come with blown fuse indication LEDs and transparent cover with recessed areas for label stickers. The assembly process is quite easy and can be done using the supplied instruction manual.