Single Reference in-ceiling/in-wall surround speaker Equipped with two 6.5-Inch bass/mid drivers and two 6.5-Inch Planar pressure-coupled low bass radiators Frequency response: 22Hz - 30kHz Equipped with two 1-inch pure aluminum dome tweeters Outer Flange size: 8.13 W x 29.75 H x 3.88 D inches