WirthCo(R) Battery Doctor Battery Quick Disconnect Caps are designed to fit top post batteries, 4 to 6 gauge wire and side post batteries with standard post adapters. They are manufactured of copper-zinc plated steel and rated 500 amperes continuous and 800 amperes surge at 12 Volts. They attach to the battery terminal by clamping down on the cap and detach by lifting the cap to remove from the battery terminal. The caps are color-coded with red and black and come as a pair. For over 30 years, WirthCo® has been a prime manufacturer of practical products for making life easier and safer. WirthCo® Battery Doctor Battery Quick Disconnect Caps are designed to fit top post batteries, 4 to 6 gauge wire and side post batteries with standard post adapters. They are manufactured of copper-zinc plated steel and rated 500 amperes continuous and 800 amperes surge at 12 Volts. They attach to the battery terminal by clamping down on the cap and detach by lifting the cap to remove from the battery terminal. The caps are color-coded with red and black and come as a pair. For over 30 years, WirthCo® has been a prime manufacturer of practical products for making life easier and safer. California Prop 65 - Warning, This product contains chemicals known to the State of California to cause cancer, birth defects or other reproductive harm.