Kessler Thermometer and Chase Instrument have been manufacturing Precision Hydrometers and Thermometers since 1934.

We are the manufacturer of SafetyBLUE Non-Mercury Precision Thermometers and Thermohydrometers. These offer an excellent alternative solution when mercury is prohibited. Many of our SafetyBLUE are now ASTM approved.

We offer a complete line of Extreme Precision Thermometers and Hydrometers. We offer customized manufacturing to suit your specific needs.

We are ISO 17025-2005 and ISO 9001-2008 accredited and a member of the ASTM committee on Thermometers and Hydrometers. We are dedicated to our customers in setting high standards and maintaining the integrity of our products. We will certify any Thermometer and Hydrometer, as well as re-certify your own instruments in our calibration lab. We guarantee fast calibration and re-certification.

Quick and reliable turnaround.


Most items are in stock for immediate delivery.

All products can be certified and traceable to NIST.