Atlas Volume Control f/Ceiling Speaker

AT Series Industry Standard Auto Transformer. High-quality auto transformer series provides  the advantages of excellent frequency response, low insertion loss and reliable performance  for volume control application in 25 and 70.7-volt systems. Attenuation is accomplished in ten  make before break steps plus positive off position. (No stop between maximum and off position  to prevent switch damage). Contacts are silver plated for noise-free operation. Features a  removable terminal block. Includes stainless steel plate, with stamped and filled or screen  printed dial scale and a skirted black knob. (White and ivory plastic plates with matching skirted  knobs also available in Decora style-see AT model description chart.) AT10 / AT35 / AT100 Series Face Plate Options

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