Fuse holders for front connection have mounted screws for 1/2" panel thickness on 200 ampere and smaller, and for 1" thick panels on 400 and 600 ampere. The 400 and 600 ampere holders fit panels from 1" to 2" thick. Back connection fuse holder terminal studs on 200 ampere and smaller fit and panel up to 2" thick. Fuse holders have a corrosion resistant finish and are not furnished with terminal lugs.