These mammoth woofers feature a vented cast aluminum basket, aluminum voice coil former and bumped and vented backplate for continuous cooling under extreme conditions. Dual flat spiders with woven and insulated tinsel leads, carbon fiber reinforced paper cone and a 7-layer high density "fat rolled" surround keep the bass tried and true. Whether you are trying to impress your friends or the judges at a car audio competition, the Big Bang Series subwoofers have what it takes!