Thomas PTFE Frio-Temp Precision Liquid-In-Glass Verification Refrigerator Thermometer, -5 degree to 15 degree C Range PTFE coated Individually serialized Tested and calibrated in a triple accredited/registered ISO/IEC 17025:2005, A2LA accredited laboratory against equipment whose calibration is traceable to NIST and DKD/PTB -5/15 degree C temperature range 0.5 degree C Division