The integral speaker amplifier can power remote speakers or driver and horn units. The units are gasketed for extra protection against dust and moisture.

Each Indoor and Outdoor Handset Station includes a front panel pushbutton for all-paging; a durable 6-foot PVC coil cord; a noise-cancelling microphone for reduced transmission of background noise; and sidetone circuitry to reduce amplification of the user’s voice into the earpiece. An electrical safety barrier is mounted inside the housing to provide intrinsically-safe connections to the handset. Multi-party stations include a durable rotary switch for party line selection.