Bose Professional MB210-WR compact subwoofers are designed for outdoor installations of background/ foreground music and small sound-reinforcement systems that require low-frequency extension down to 37 Hz. The MB210-WR subwoofer features two (2) 10-inch high- excursion woofers, derived from the award-winning Bose Professional F1 subwoofer, in a compact, exterior-grade plywood enclosure optimized for outdoor, fixed-installation applications.