Extech HD200-NIST Thermometer with Nist Type K temperature range: -328 to 2501DegreeF (-200 to 1372DegreeC) IR temperature range: -22 to 1022DegreeF (-30 to 550DegreeC) Data logs up to 18,000 readings on each channel Display [T1, T2, T3(IR)] or [T1-T2] or [T1-T3] or [T2-T3] Differential T1-T2 display for HVAC/Superheat measurements