UL Class and midget fuse blocks accept fuses sized and rated according to UL Class or midget specifications. They have an open top for access to fuses, clips or studs for securing fuses within the block, and terminals for connecting to the circuit. These fuse blocks are either bolted down or mounted on a DIN rail to hold them in place. They're commonly paired with fuse box covers to enclose the fuses and prevent accidental contact. They are nonindicating, so there's no visual signal when a fuse is blown.