Lovely Apple 2.4GHz 2.5inch wireless baby monitor LCD Screen Type: 2.5 inches TFT-LCD Transmission Frequency: ISM 2, 400~ 2, 483 MHz Operating Frequency: 2414MHz; 2432MHz; 2450MHz; 2468MHz Transmission Power: 10mW/ CE; 2mW/ FCC Unobstructed Effective Range: 100m( Min.) Modulation Mode: FM Operating Temperature: -10 ~ + 50( Degree C) / + 14~ + 122( Degree F) Operating Humidity: d85% RH Battery Working Time: 5 hours