Priced and Sold as a Pair Driver (810): 8 in. 15W dual cone driver with 10 oz. magnet, frequency response of 54Hz-11.6kHz (+-6dB) and 50Hz-20kHz (+-6.6dB), and average sensitivity of 97.9dB measured 1W/1M. Conical dispersion 95 degrees. Transformer: Dual voltage 25V/70V transformer with taps at .25, .5, 1, 2, 5W. Grille with Subplate (1 x 2): Fine-perforation grille provides maximum free-air space for excellent sound transmission while maintaining an unobtrusive appearance in new or existing tile ceilings. White. Enclosure (0.147 cu.ft.): Steel backbox with speaker leads that exit through a metal clamp for fast connection. Black. Mounting Aid: Patented integral T-bar supports neighboring cut non-tegular ceiling tile. Restraint tab and hole for two-cable code compliance (cables not included).