Price Match Guarantee Polk Audio 80F/X-LS High Performance In-Ceiling Surround Loudspeaker with Dual Tweeters and 8" Driver (Pair) The Polk Audio Vanishing Series in-ceiling loudspeakers feature a precision-engineered, minimally flanged design and Polk's exclusive Sheer-Grille, which protrudes only 7mm from its surroundings. Installing virtually flush in your ceiling, the Polk Audio Vanishing Series in-ceiling loudspeakers offer a one-cut, drop-in installation and rotating cam stabilizing system