PRO-WIRE IWIMP100WVW Impedance-Matching Volume Controls White • For Full Audio System • Adjust Volume Without Leaving The Room • Rotary 12-Position Impedance-Matching Auto Former • 1X, 2X, 4X, 8X & 16X Impedance Multiplier • Smooth Transition Between Volume Steps • Freq Resp: 20 Khz - 20 Khz ?1 Db • 2.63 Mounting Depth • Includes Decorator Wall Plates • Limited Lifetime Warranty • White