Boston Acoustics VRX Black (pr) VR Surround Wide Dispersion Home Theater Surround Speakers 4.5" SATELLITE SPEAKERS 4.5" ACTIVE WOOFER; 4.5" PASSIVE RADIATOR; DUAL 1" VR(R) TWEETER WITH ANODIZED ALUMINUM DOME, AMD(TM) &amp; EXTRUDED ALUMINUM HEAT SINK; HIGH-PERFORMANCE WIDE-DISPERSION HOME THEATER SURROUND SPEAKERS CAN BE USED AS DIRECT-RADIATING OR DIFFUSE-FIELD SURROUNDS