Not 100% sure, but at a 50, 000 hour life expectancy I may not live long enough to find out. I only use mine maybe 4 hours a day on average. I still have @ 30 years to go at this rate. Seriously though, ive put mine through hell and never had an issue other than coil cleaner strippong the aluminum on one. Great lights for @ $100 and always charged and ready for the next call.