Bose MB4 Floorstanding Speakers user reviews : 4 out of 5 - 1 reviews - audioreview.com
Bose Panaray MB4 bass modules | eBay
Bose Gym Sound System Panaray 402 Series IV Loudspeakers, MB4 Modular Bass Loudspeaker, ControlSpace SP-24 Sound Processor and QSC GX Series Amplifiers
Panaray® MB4 Modular Bass Loudspeaker - Bose Portable PA Encyclopedia