The Extech RHT510 thermo-hygrometer psychrometer measures relative humidity, temperature, dew point, and wet bulb. It includes a general purpose bead wire Type K probe for temperature measurement up to 480°F, and can measure up to 2372°F with other probes. Features include min/max function to store highest and lowest readings, data hold, auto power off with disable, and backlit LCD display. Specifications: humidity 10–95% RH (±4% accuracy), air temperature 32–122°F (±2.5°F), Type K temperature -148–2372°F (±0.4% + 1.8°F), wet bulb 22.2–120°F, dew point -13.5–120.0°F.