This Harmony measurement probe is an accessory for control relay. This measurement probe is an accessory for measurement and control relay, ideal for monitoring of liquid level. It applies to a wide type of industrial automation applications. It is made of PUC protective shell and stainless steel electrode. It is compatible with control relay RM35LM33MW and RM4L. It provides an automatic detection of abnormal electrical values before they incur serious damage to machinery thus reducing your maintenance and downtime costs. It provides automatic shutdown