Lowell's 100LVC Volume Controls are installer-friendly and provide high quality level adjustment of single or multiple speaker lines. The Lowell 100LVC is a single gang unit that mounts in a minimum depth of 2.125". All units have phoenix-style removable screw termination strips for pre-wire with capacity for 14ga wire. It is 3db/step or 1.5db/step as noted. This 100W autoformer attenuator (volume control) with 3dB steps for great for use with a 100/70/25V speaker line. It includes 1-gang standard wall plate with a rotary knob and is ETL Listed.