The HM Digital SP-1 TDS/EC Sensor Probe for Panel Mounted Controllers features a durable plastic construction and stainless steel sensors. The sensor probe includes a 1/2 inches threaded NPT bushing and 9.8 ft. shielded cable. The threaded bushing is detachable from the cable. The connector has four points. The cell constant is 1.8cm-1. The sensor is to be used for PS-100, PC-100, PS-200, and PS-202.