Hey mate its one of these
HOLDEN COMMODORE 12'' SUB SUBWOOFER BOX VX VT LS1 GEN 3 - eBay Subwoofers, Audio, Video, Car Parts, Accessories, Cars, Bikes, Boats. (end time 26-Apr-10 16:25:01 AEST)
Brand New 31 Litre 12'' Subwoofer Box to fit Holden Commodore VT and VX Sedans. Made from Fibreglass...