Features: 1) Temperature range: -10 to 50 Centigrade 2) Indoor hygrometer range: 25% RH to 98% RH 3) Maximum or minimum memory temperature and humidity 4) For Celsius and Fahrenheit conversion 5) Use one 1.5 volt AA battery 6) Overall dimension: L135 x W78 x H21 Inner packing: plastic Bag Outer packing: 25pcs/carton Carton dimensions: 268 x 226 x 224 G.W.:2.6kg