2022 UPGRADED: The insulated nylon base is flame-retardant. This Bus bar is made of zinc alloy and brass with good electrical conductivity.Each bus bar includes a cover to protect connections from protect against damage or corrosion. For Superior Insulation And Strength KEEP TIDY: With these heavy duty power distribution blocks you can organize your wiring cleanly. (Maximum amplifier per circuit: determined by the connected wires. Maximum working voltage is DC 48V & up to 250 Amps.) EASY TO INSTALL: you just need to use the screws to fix the battery terminal distribution block in their respective positions, then use wiring on the screw, and then fix the nut, easily done CONFIDENT BUYING: The power distribution block holds wide cables securely to keep the wires neat and organized. If you have any questions, feel free to write to us via . We are always here each day We will do our best to assist you. WIDELY APPLICATION: The power distribution block is widely used in12-48V auto and marine wiring, trucks, RVs, boats,Trailers and other industrial equipment.