18 in. compact subwoofer. 350 W (continuous), 1400 W (peak) power capacity. The rugged enclosure is constructed from 19 mm (.75 in) MDF (Medium Density Fiberboard) using advanced adhesives and mechanical fastener technology for durability and improved low-frequency performance. The enclosure is covered in black carpet. A top mounted, cast aluminum 35 mm pole mount receptacle can receive an optional SS3BK pole to facilitate use of the JRX218S as a base for a midhigh speaker cabinet. Non-resonant, all steel handles are used. Attractive 18-gauge perforated steel grille protects components from damage.