Athena Technologies AS-B2 Audition Series 2-Way Bookshelf Speakers with 6.5" Woofers (Pair) Pair of 2-way bookshelf/satellite speakers Each speaker uses a 1-inch Teteron dome tweeter and a 6.5-inch injection-molded composite polypropylene woofer with rubber surround 50 to 20,000 Hz frequency response (+/-3 dB); 91 dB efficiency Rated for use with amplifiers providing up to 125 watts per channel Measures 7.9 x 15.8 x 9.5 inches (W x H x D) each