The black V221-S Passive Bass Reflex Subwoofer from RCF is equipped with two 21" precision woofers mounted in a front-loaded configuration. Each woofer features massive vented magnets and 4.5" copper voice coil. It is capable of handling up to 4,000W AES power and produces a maximum SPL of 143 dB. The subwoofer's compact design ensures an efficient acoustic response down to 25 Hz.

The cabinet is constructed using baltic birch plywood and coated with weather-resistant, textured polyurethane black paint. The front steel grille is epoxy powder coated. The unit can be installed in either horizontal or vertical configuration. The enclosure features four side recessed handles and rubber feet.