Turnigy Voltage Detector is very accurate and easy to use and only weighs 6g. The 3~8S voltage detector will give a warning buzzer as well as LED indication for High, Average, Below average, and Low voltages on your Lipoly battery. The buzzer is also quiet loud. Its varied warning range is great for those with gliders that need time to bring the plane down from a high altitude. Turnigy voltage detector has polarity protection. Operating Voltage : 9~33.6V Mått: 30x17x12mm Weight: 6g