The HI-98121 is a waterproof combination tester capable of measuring ORP/Redox and pH and is a popular option for operators carrying out spot checks or testing on location. Designed for use out in the field and in murky conditions, the meter is sealed against humidity, floats in water and has a bright green casing making it easily visible in low level of light. It has a replaceable electrode with a stainless steel round connector meaning there are no pins to bend or break during replacement. The exposed stainless steel temperature sensor facilitates faster and more accurate temperature measurement that is easy to record using the hold function that freezes the reading. This pocket-sized portable combination tester also features a dual level LCD screen that displays simultaneous readings, calibrates automatically and has automatic temperature compensation.