This radio is helpful for the following circumstances: security guard, supermarket connection, construction area indication. It is also helpful for field survival, biking and hiking. It is very easy to use these. All you need is to turn these two to the same channel (16 channnel to be chosen), push a button, and you can hear from your mate. *16 channel *1500mAh Li-ion battery *50 CTCSS/105 CDCSS *VOX Function *Voice Prompt *PC Programming *Emergency Alarm *Intelligent Charging *Battery Save *Low Voltage Alert *Time-out Timer *FlashLight Specifications: Channel Capacity: 16 Channel Spacing: 25KHz Operated Voltage: 3.7V Battery: 1500MAh Li-ion Battery Life: About 8 hours Frequency Stability: ±2.5ppm Operated Temperature: -30°c-+60°c Antenna Impedance: 50Ω Communication Range: about 2-4km Transmitter: RF Power Output: 3W Modulation: F3E Spurious Emission: ≤65dB FM Noise: ≤-45dB(W) ≤-40dB (N) Audio Distortion: ≤5% Transmitting Current: ≤1.3A Receiver: Sensitivity (12dB SINAD): ≤0.20 uV Selectivity: 55dB/50dB Intermodulation: ≥65dB Adjacent Channel Selectivity: ≥60dB Spurious Response: ≥60dB Audio Power Output: 1000mW Dimensions (L×W×H) (with battery, without antenna): 10×50×32 mm Weight (with battery/antenna): 198g