BIC 5 1/4in 2-WY IN-WALL SPEAKERS Polypropylene woofer with high-compliance surround, 1" Ferrofluid cooled soft dome tweeterFrequency response: 60Hz-21kHzSensitivity: 90dBOverall: 7 1/2" W x 11" H x 3" D; cut out: 7 1/4" W x 9 5/8" HIncludes 3-year transferable warranty