Electrical Ratings Labeled UL 707B. Rating: 500A intermittent, 310A continuous, 6-36V DC Electrical ratings on UL labels are conservative. Use with either alternators or generators. Make before break design permits operation through the three On positions with the engines running. Engines should always be shut down before turning to Off. Heavy-Duty Construction Vapor proof, weather-, dust- and corrosion-resistant. Durable, fracture-resistant high temperature plastic case, knob and insulator. Switches conform to uscg Resistant to impact, and temperature extremes. Heavy duty copper stud terminals, with brass hex nuts. Can be surface mounted, or installed through a 3 5/16" diameter hole in the panel. Dimensions: Flange: 6" (152.4mm) diameter, overall height 2 5/8" (66.7mm). Terminals: 3 copper studs, 3/8" (9.5mm) diameter.