1/4 DIN panel mount pH/ORP controller/transmitter with dual SPDT Hi/Lo relays, manual set points and calibration are via potentiometers. Features a 4-20 mA current output and has an external pH/ORP select switch. Display is a large LCD. Connectors are a BNC and spade lug screw type connector blocks. Meter requires a Pt-100 ATC or a simulation resistor for temperature. Power 115/230V AC.