UL, CSA, TUV, VDE. Stainless Steel Terminal Boxes, KL Series. The KL Series enclosure from Rittal is folded and welded from a single piece of 1.25 mm stainless steel. The cover of the enclosure has a channel with a foamed-in PU seal providing IP66 protection. The inside of the enclosure has profiles with mounting holes for easy installation of a chassis plate or DIN rail. Retaining cord Profile strips on both sides of enclosure ensure maximum mounting depth is achieved Facilities for mounting C rail and 'top hat' DIN rail Polyurethane sealing gasket Material 304 / 1.4301 stainless steel