The ADI.W300X is a shallow mount, high power, high stroke subwoofer designed for use in wall cavities, between floor/ceiling joists, and other shallow locations.  It features a 65mm diameter voice coil, our patented (US Pat 7,039,213) XBL™ motor design, a 250mm OD spider, and a reverse-roll surround to provide minimum clearance for any grilles required.  It uses a thick-wall stamped frame, tight-mesh wire grilles over all openings to keep debris out, and a flat, honeycomb piston for a cone.  All this in a package with a mounting depth of less than 87mm.