The PK-7 power supply is housed in a rugged metal chassis and has the capacity to power up to 12 RS-701 headsets. It supplies 24 volts DC at 0.4 amp to the system. The fully regulated, current-limited unit also provides proper termination for the intercom system. The PK-7 features both short-circuit and reverse polarity protection.

The SMQ-1 is an all metal beltpack providing full duplex two-way communication.