Applicable for home, office, car, schools, hotels, laboratories, kindergartens, aquaculture, instrument workshops, libraries, factories, and spaces equipped with air conditioning. This portable hygrometer thermometer measures indoor humidity and temperature in real time, helping to adjust humidifier, dehumidifier, and humidistat settings. Ideal for monitoring living conditions and supporting health by helping prevent colds, dry skin, asthma, and mold. Fast response with measurements taken every 10 seconds, featuring 24 sensitive vents for accurate and updated readings. Wide measurement range: temperature from 0.0 to 50.0°C, humidity from 10% to 99%. (Please allow for a certain degree of measurement error.) Temperature display in Celsius only. Bright black front panel with clear LCD display for easy reading, even from a distance. Humidity measurement accuracy: ±5% RH. Humidity display resolution: 1% RH. Temperature measurement range: 0°C to 50°C. Temperature measurement accuracy: ±1°C. Temperature display resolution: 0.1°C. Panel cutout installation size: D42mm. Operating voltage: 1.5V, uses one LR44 button cell battery. Color: Black. Material: ABS plastic shell. Dimensions: 45 x 15.5mm. Package includes: 5 x digital hygrometers, 5 x button batteries.