Hadron 250 plus (lipo battery version). Need to press the fire button 5 times to power it up. Both of my DNA devices will automatically power down after a period of inactivity, but the Hadron does it within a few (less than 5) minutes, instead of the original much longer delay. Regular use for a little over a year and the new behavior only started about two weeks ago. Never charged the cell in the unit, alternated between 2 cells that were recharged in an external charger.