CALL A.WIHARTA 081294124885 085778084789 087784022201 The Hanna Instruments HI 99141 Portable pH and Temperature Meter for Boiler and Cooling Towers is a waterproof, portable pH/ temperature meter supplied with a flat tip probe specifically designed for boiler and cooling tower applications. The Hanna Instruments HI 72911D pre-amplified double junction pH probe features a recessed flat tip that is easy to clean and prevents solids in solutions from collecting on the sensor. The titanium body of the Hanna HI 72911D functions as a potential matching pin for increased stability of readings and extended sensor life.