The Retro 8 Subwoofer is 8" high performance 70v/100v/8-ohm retrofit subwoofer ships complete with all hardware for sheetrock or drop tile installation included. Front mounted selector switch with 8-ohm transformer bypass. 70 volt input taps of 7.5, 15, 30 and 60 watts. The ported enclosure design combines a high excursion voice coil and bump-up back plate with vented pole piece to provide rock solid output even under the most demanding conditions.