Item Description
Power Switch Slide to turn the GT-531 ON or OFF.
Charging Jack Plug Universal AC to DC converter module into the jack to
charge the internal battery.
Serial Port Used for RS-232 or RS-485 serial communication (Section 6).
Iso-kinetic Probe Reduces count errors due to mismatched sample flow velocity.
Temp/RH Connector Used to connect an external temperature and humidity probe.
Display Adjust Adjusts the LCD display contrast.