Meets all UL 20 requirements, Federal Specifications WS 896. Industrial design cam action mechanism insures quiet switch action. Color-coded faces identify amperage: blue=15 amp, red=20 amp, green=30 amp. Automatic grounding system eliminates need for bonding jumper in grounded metal enclosure. Back and side wire terminals accept up to #10 solid or stranded wire. Ground screw terminal standard. 0.050" thick steel mounting strap zinc-plated for corrosion resistance. 120/277V AC rating ideal for fluorescent lighting fixtures typical in commercial applications. Combination slot/Phillips head mounting and terminal screws ease installation with power screwdrivers.