The SPK-C611 is a pair of two-way open-back speakers designed for mounting in the ceiling. They have an infinite baffle design and aluminum grilles. These speakers are great for use in conference rooms, boardrooms, classrooms, hotels and restaurants. Limited Supply While They Last; Open Back; Woofer - 6.5"; Tweeter - 1"; Impedance - 8O; Freq Response - 55Hz to 20kHz