Specification: Item type: weather clock. Material: ABS Size: Weather clock: approx. 9.7 x 15.2 x 4.5 cm / 3.8 x 6 x 1.8 inches. Sensor: approx. 5 x 9.6 x 2.5 cm / 2 x 3.8 x 1 inches. Weight: approx. 445 g / 15.7 ounces. Use: weather clock. Battery: weather clock, sensor, dry battery, AA x 2 (battery not included). Indoor and outdoor humidity range: 20% to 95% RH Temperature: Measuring range of indoor temperature: -9.9°C (14.2°F) to 50°C (122°F). Measuring range of outdoor temperature: -40°C (-40°F) to 70°C (158°F). The temperature can be switched to °C or °F. Wireless outdoor sensor: 3 channels can be connected. 433.92 MHz RF transmission frequency. Up to 60 metres transmission range in open area. Package list: 1 x weather clock (battery not included). 3 x sensors (battery not included). 1 x user manual (English language not guaranteed) Features 3 transmitters: This weather clock is equipped with three transmitters that can display three sets of temperature and humidity data on the same screen at the same time. Optional hour system: the display of this weather clock is optional in the 12-hour and 24-hour system, the permanent calendar lasts until 2099. [7 LANGUAGES] The weather alarm clock has 7 optional languages: English, German, Italian, French, Spanish, Dutch and Danish. Multifunctional: the weather forecast clock has two alarm sets, snooze function, low power consumption reminder, indoor comfort display and reminder of mould hazard indoors. Battery operated: the weather clock thermometer only uses batteries, without power supply, convenient and easy.