Finally, a sonically superior magnetic core coil! The Super Q line features a specially shaped core that allows for optimal magnetic performance and increases the coil's effective permeability. The result is extremely low DC resistance, reduced distortion and very high saturation levels. The coils are encapsulated in a plastic housing, which eliminates any magneto striction distortion and makes mounting a breeze. The 500 watt power rating makes these coils perfect for high power prosound applications. All coils measure 4-1/2" L x 1-5/8" H and are made in the U.S.A. Recommended for frequencies 0Hz - 3000 Hz.