CM-800 COMMAX Master       CM-801 COMMAX Slave

Functions:
Calling between Master and Slave
Enable talking by TALK button
Privacy button on Slave
Call tone and volume adjustable
Specification:
2 wires between Master CM-801 and Slave CM-800
AC Adaptor DC 12V (200mA) connected to Master only

Wiring distance 300 meters with copper wire 0.65mm  

Dimension 183x169x41 (mm)