Compact, lightweight enclosure - Easy to transport, setup and breakdown. Small footprint takes up considerably less space than traditional bass cabs required for same performance. Fits between legs of power stand. Interlocking feet on the modules make it easy to securely stack up to four modules together on their sides. Highly efficient speaker design - Two 5 1/4\" (13.3 cm), high-output, high-excursion drivers produce deep strong bass from an elegant small enclosure. When connected to power stand, active equalization circuitry automatically adjusts bass signal appropriately. Rugged, twist-lock connector on bass module lets you link two modules together.