A range of high quality attenuators supplied complete with plastic surface mount back box. The stylish ABS faceplate is fitted with a matching plastic knob. Each attenuator is fitted with a relay for un-muting output remotely from a fire alarm panel. Attenuation in 10 steps: 8 x 3dB and 2 x 6dB steps. |24V relay fitted for remote fire alarm un-muting.