Key Specifications/Special Features: GSM900: 890 to 915MHz, 935 to 960MHz Channel space: 200KHz User line, bell signal: in line with GB/T 15279 Maximum power: 0.25/2W Consume: immobility 25mAh and transmission 400mAh Sensitivity: -105dB Dial tone frequency: 450MHz (standard) Surrounding temperature: -10 to 40¡ãC Relative humidity: 45% to 90% RH (without frost) Atmosphere pressure: 86 to 106kPa Environment noise: