This hygrometer is compact and can be placed indoors to measure indoor temperature and humidity, especially for families with small babies. Features: Constructed of weather-resistant and shatterproof materials for increased durability during use. Accurately measure temperatures from -20 to 120 (-30 to 50). Bold black lettering with large numbers and two black pointers makes reading easier. 2.24-inch indoor and outdoor temperature meter can be mounted in greenhouses, warehouses, baby rooms, offices, laboratories, balconies, gardens, terraces, etc. No batteries are required. For the most accurate readings, place them out of direct sunlight. Specifications: Color: green A, green B, gold, silver (optional) Material: aluminum Temperature measuring range: -20 to 120 / -30 to 50 Humidity measuring range: 0-100RH Item size: 57 * 57 * 12mm / 2.2 * 2.2 * 0.5in Package size: 80 * 60 * 13mm / 3.1 * 2.4 * 0.5in Package weight: 20g / 0.7ounce Packing List: 1 * Hygrometer