... size, easy to use.5. LCD display power supply,low battery,signal link,volume and so on.6. Remote electronic laser ... upgrading.7. Pen designed,instead of any other MIC.8.Lithium Battery Environmental protection. :3.7V/900mA9. It can work for 30 ... hours: 30hours Standby time: 60days Working Voltage: 3.7V Alkaline battery Working Distance: ≤80 meters Working Temperature: -30-50°C Weight ...