RCF LF21N451, Woofer 21", 1500 Watt RMS / 8 Ohm | MUSIC STORE professional
AccuGroove Whappo Grande Bass 21" Subwoofer – AccuGrooveLLC
RCF LF21X451, Woofer 21", 2000 Watt RMS / 8 Ohm | MUSIC STORE professional
MVP21 GETSHOW 21 inch Powered Subwoofer Speaker Built-in Amplifier Active professional loudspeaker system
Amazon.com: Sound Town 21” 1000W Cast Aluminum Frame Woofer (Low Frequency Driver), Replacement Woofer for PA/DJ Subwoofer Cabinets (STLF-21500A) : Musical Instruments
KS21 Single 21 Inch High Excursion Professional Audio Subwoofer Speaker for DJ Outdoor Concert - Buy KS21 subwoofer, dj subwoofer speaker, line array speaker subwoofer Product on Sanway Professional Audio Equipment Co., Ltd.
MT21A Built-in DSP single 21" Self-powered Subwoofer with Compact Cabinet Box - Buy 21" subwoofer, single 21 inch subwoofer, self powered subwoofer Product on Sanway Professional Audio Equipment Co., Ltd.