Looking to add a subtle hint of vintage style on your wiring needs? These nuts are made to look like old vintage stock and made of solid brass for best electrical performance. Works on most AC Delco, Autolite, Bosch, & Motorcraft (14mm, 18mm, 7/8" & 1/2" Pipe), Champion 14mm & 18mm spark plug with removable top nut (metric 4mm thread). Included as well are two nickel-plated Rajah ring terminals perfect for any 7mm copper core spark plug wires. Simply strip the end of your spark plug wires, insert the wire into the screw end and tighten the terminal on. The brass nut is what holds the ring terminal onto your spark plug.