I made the mistake of falling asleep in my lavvu with it still on and it was still going strong in the morning. i reckon all in i got 10-11 hours before i changed the batteries. its a bit of a fiddle to do in the field but not impossible. All the internals are loose but its not complex to put back together. I reckon theoretically will continual use you should see 10 hours based on 2x cr2016 rated at 100 mah each. used in bursts it will be slightly better as the chemistry has chance to recover. plenty for a weekend and with 1 change of batts you could probably go a week if used sparingly
