From the seller:

ClearCom PL Pro PS232, full system including packs and head sets. 7 Belt packs 6 Prograde headsets 2 Cheap wire headsets The Clear-Com PS-232 is a single rack space, one- or two-channel intercom power supply which can provide 1 amp (2 amps peak during call signals and other temporary events) at 30 Volts DC to operate Clear-Com beltpacks and remote stations. This power is supplied to either or both channels, and will support up to 40 headset stations or 15 speaker stations. Clear-Com's advanced fail-safe design can sense the difference between a short or an overload to optimally protect itself. Power is restored in as quickly as 1/2 second, depending upon whether there was a single or multiple short or overload. The other channel continues to operate normally. The PS-232's advanced fail-safe circuit will bring the power back up even under full load conditions. LED indicators signal a fault on either channel. A line level program input offers a master input level. Individual program selects, each with its own send level, are provided for each channel. Use of a switching power supply allows the PS-232 to operate with any AC line voltage from 90 to 240 Volts AC at 50 or 60 Hz. The unitized aluminum chassis and extra thick front panel with integral rack ears result in reduced size and a lighter weight package that maintains legendary Clear-Com ruggedness.