TPU35B,are wall-mounted telephone paging amplifiers rated at 35 watts. This group of TPU amplifiers permits paging from telephone and/or microphone. Music input through an RCA jack or screw terminals. Voice-activated, variable level, music mute with fade back after page. All the TPU amps in this group include a night ringer which sends an electronic ringing tone signal through all speakers, alerting personnel of incoming calls during non-business hours. Jacks are also provided to bridge two TPU amplifiers to double the number of inputs and outputs.