Technical parameters: Natural wet bulb temperature, black globe temperature, air temperature, the level of three probes was hung on the same installation. ★ natural wet bulb temperature probe: ◆ probe shapes: cylindrical ◆ probe diameter: 6 ± 1mm ◆ Minimum probe length: 30 ± 5mm ◆ Range :5-40 ℃ ◆ Accuracy: ± 0.5 ℃ ★ Black Ball: ◆ diameter: 150mm ◆ The average radiation coefficient: 0.95 (not polished black ball); ◆ Thickness: The thinner the better; ◆ Measurement range :20-120 ℃; ◆ accuracy :20-50 ℃ ± 0.5 ℃ 50-120 ℃ ± 1 ℃ ★ air temperature probe: ◆ Measurement range :10-60 ℃ ◆ Accuracy: ± 0.5 ℃ Main features: ◆ Automatic storage of data records up to 100 hours; ◆ Data Analysis computer software; ◆ All Chinese operation menu; ◆ meet ISO7243, "high temperature grade" (GB/T4200-1997) and "workplace hazards of occupational exposure limits" (GBZ2-2002). Height 27mm Weight 130g with battery