Copper Solderless Lug 6-14 AWG with 3/16" Mounting Bolt : Made of 99.98 pure electrolytic copper. Steel-plated screws to prevent rusting. 25 to 70 ampere size have slotted head screws. Larger sizes have hex head screws. Rated 600 volts max. UL 486 Listed. Temperature rating 90 degrees C.