I have a dual (quantity, not brand) 12 inch sub box for sale. Was used to house 2 JL audio W6's. Has a divider between the two subs. Also filled with poly-fill. PM's are usually responded to immediately. Approximate External Dimensions are Width, depth, height 32 x 17-5/8 x 14 At its widest parts Approximate Internal Dimensions are 14.5x15.5x12. Cubic feet (per side) is about 1.56 if my calculations are correct.