TWO IN ONE: The mini digital hygrometer thermometer features a built-in probe, electronic thermometer, and hygrometer for measuring temperature and humidity for indoor use. WIDE TESTING RANGE: Temperature measuring range: -58°F to 158°F, humidity measuring range: 10%–99% RH. HIGH PRECISION DISPLAY: Temperature measurement accuracy: ±2°F, humidity measurement accuracy: ±5% RH. EASY TO INSTALL: This hygrometer gauge helps monitor current temperature and humidity. Embedded opening size: 1.81 x 1.06 inches. If the size is not suitable, it can be secured with double-sided tape. WIDELY USED: The indoor thermometer hygrometer is suitable for use in greenhouses, gardens, guitar cases, incubators, brooders, offices, cellars, refrigerators, closets, and other locations requiring temperature and humidity monitoring. Color: Black Material: ABS Size: Approximately 48 x 28.5 x 15.6mm Package Contents: 6 x Digital Thermometers Note: Light reflection and different displays may cause slight variations in the color of the item shown in the picture compared to the actual product. Measurement error allowed: ±1–3cm.