Mini Walkie Talkie Two Way Radio Stable Signal 3.7V with Bluetooth Wireless Headset for Home Commercial Security Item Type: Mini Walkie TalkieMaterial: ABSBluetooth headset: Bluetooth version: Bluetooth V4.2+EDR Support mode: HSP/HFP/A2DP/AVRCP Transmission distance: about 10 meters Charging voltage: DC 5V Incoming current: 0.5A-1A Standby time: about 18-20 hours  Charging time: about 1-2 hours Battery type: 1 x 200mAh lithium battery (built in battery) Walkie talkie: Bluetooth version: 4.0-4.2 Output power: <2W Number of channels: 32 Operating temperature range: -20℃ ~60℃ Rated voltage: 3.7V Battery capacity: 1 x 1100 mAh lithium battery (built in battery) Channel interval: 12.5 K/25KHz External dimensions: Approx. 106mm x 33mm x 22mm / 4.17 x 1.3 x 0.87in Antenna resistance: 50Ω