Using the Mag switch to tap on and off for each flight, the Micro might translate into one or two months of normal use per battery change, while always maintaining a safety margin of three days to look for a lost bird. You can leave your battery in the Micro for up to six months. The transmitter keeps track of cumulative transmission time to estimate remaining battery life, even when not transmitting. If you are getting an early double beep warning, it is possible that the memory inside the transmitter was not reset when the battery was last changed. To reset the memory, either turn the transmitter on with the magnet before changing the battery or short the contacts every time a battery is changed.