A battery bar is a small metal bar that is used to interconnnect individual cells in the homebuilt construction of a racing-type battery pack, since many matched cells are sold as a disassembled set. They are usually copper and often gold- or silver-plated to aid in current flow. Some years ago, Trinity Corporation created a still-popular line of battery bars called "Lennon Lugs," so named because the circular contacts joined by a horizontal bar greatly resembled the round, "hippie" eyeglasses often worn by musician and composer John Lennon.