I'm not entirely sure in run time. I can say this, I've yet to have it run out on me during a ride. I don't think I've done much more than 2 hrs rides at night over the past few yrs. I've done C&D, R&I and Oskar Blues with it and never ran out. We own 3 of them (oldest one is 4 yrs old) and occasionally when I leave house and I'm unsure if its fully charged, I just put a 2nd one in my back pocket JIC. FWIW I also run a L&M Seca 1300 on my bars. So I can toggle back and forth with my lights to maximize run time or light needed for techy riding. Oh and I've also used the light on road rides too. Those may be more than 2 hrs?? Overall, I have zero complaints. Its served its function, been handy and is pretty cheap
Later,
CJB