Split Bolt, Copper, Tin Plated, No. 1 Stranded Conductor (STR) - 250 kcmil, Made from high strength copper alloy to provide premium electrical and mechanical performance, Tin-plated to inhibit corrosion and oxidation, Offered with dual rating for use with aluminum or copper conductors, Nut hex provides correct fit with socket, box, or open end wrenches resulting in proper torquing of electrical connection, Free floating pressure bar separates conductors of dissimilar materials for secure connection on a full range of conductor combinations, UL Listed and CSA Certified for use up to 600 Volts and UL temperature rated 90 Degrees Celsius.