H-B FRIO-Temp Freezer Verification Thermometer; -30 to 1C (B61004-0300) Range: -30 to 1C; divisions: 0.5; length: 135mm; accuracy: 0.5C Enviro-Safe EnviroKleen certified environmentally safe liquid fill is non-toxic, non-hazardous, and biodegradable PTFE safety coated for added safety; designed for use in freezers