Digital Temperature & Humidity Meter | -20-60°C PSFS3003 How often do I need

How often do I need to calibrate

Air flow volume: 270m³/h

A great set to practice with basic number sense

And when friends and relatives drop by to spend a night or two

Up to 60 pairs: Children's shoes

Digital Temperature & Humidity Meter | -20-60°C PSFS3003 How often do I needSPECIFICATIONS: Usage: Industrial Temperature Resolution: 0. 1C 0. 1F Temperature Measuring Range: 20C~60C Temperature Humidity Tester: Thermometer Style: Handheld Storage Environment: 20C to 60C: 0% RH 90%RH Screw: M12*1. 5 Refresh Rate: 2 times second Pyrometers: Humidity Meter Power Type: AAA battery Power Source: 3*1. 5V AAA battery (Not Include) Package Size: 250*90*55mm Origin: Mainland China Operation Environment: 0C to 50C Max Measuring