Check the listing for details. Blastking PROFILE21 21" 4000 Watts High Output Woofer. Condition: New. Listed at 399.99 USD. Sold Individually The BlastKing Profile series brings high output, low frequency woofers in 12”, 15”, 18” and 21” options. These transducers are capable of very low frequencies and are intended for use in a reflex or horn loaded cabinets. They are all made in a high-quality die cast aluminum frame and boast a heavy-duty ferrite magnet that allows for increased power ratings. The Profile transducers are perfect for those needing high level, low frequency output transducers with very low distortion. Features 5” Voice Coil 4000 Watts Program Power 97.2 dB sensitivity 32 Hz - 1500 Hz frequency response Forced air ventilation General Specifications Basket Diameter: 533 mm / 21 inch Rated Impedance: 8 ohm 2000 Watts Rated Power Handling4000 Watts Program Power Sensitivity: 97.2 dB Frequency Range: 32-1500 Hz Magnet Weight: 200 Oz Magnet Composition: Ferrite Magnet Voice Coil Diameter: 127 mm / 5 inch Basket Materials: Aluminum Shipping Information Net Weight: 22.8 Kg/ 50.3 Lbs Barcode: 686811893668 View PROFILE21 Datasheet