EATON Bussmann Series Class J modular fuse blocks enhance safety for any panel or electrical system design and are available for the full class J fuse amp range. All blocks are available as 1-pole versions that snap together at point of use or as factory configured 2 and 3-pole versions. All blocks are equipped with a fuse clip reinforcing spring to minimize temperature rise while maintaining reliable surface contact between the fuse and clip over the block's service life.