Features: Display indoor/outdoor temperature and time at the same time. Adopt wireless technology,you can know outdoor temperature in indoor receiver. Record max/min indoor and outdoor temperature. 12H/24H time format, / temperature unit for selection. Can be placed on the table or hung on the wall. With portable transmitter to sensor outdoor temperature and transmit within 100m without obstacle. Powered by 2 1.5V AAA batteries(Not included). Specifications: Material: ABS Color: Black Display: 94 * 54mm LCD Display Indoor Temperature Measuring Range: 0~50 / 32~122 Outdoor Temperature Range: -20~70 / -4~158 Temperature Accuracy: 1 Indoor Temperature Detection Period: testing once 30 seconds Outdoor Temperature Detection Period: testing once 57 seconds Function: Time Display, Indoor/Outdoor Temperature, / Switchable, 12H/24H time format, Separated Transmitter Battery of Transmitter: 2 * 1.5V AA Batteries(Not Included) Temperature Clock Power Supply: 2 * 1.5V AAA Batteries(Not Included) Size of Transmitter: 130 * 40 * 22mm / 5.12 * 1.57 * 0.87in Hygrometer Clock Size: 150 * 86 * 23mm / 5.91 * 3.38 * 0.91in Transmitter Weight: 47g / 1.64oz Temperature Clock Weight: 122g / 4.30oz Package Size: 16 * 14 * 3cm / 6.30 * 5.51 * 1.18in Package Weight: 259g / 9.12oz Package List: 1 * Temperature Clock 1 * Transmitter 1 * User Manual