JBL’s MTC-300BB12 Three-Cubic-Foot Backbox features extra-thick 16-gauge metal construction and a thick resonance-eliminating lining that also provides extra bass response. Made for the Control 300 Series 12″ Drivers, this backbox has a dual-mounting system for baffle and knockouts on all four sides.

This back box has a five-year warranty from JBL Professional.