Bests & Worsts Reviews from Amazon

Lumens = the total light output. Have you been to the Cree website? XM-L and XM-L2 are only rated for 1000-1100 lumens or so, depending on which one. Flashlight hobbiests have experimented and gotten as much as 1400 lumens from an XM-L by using twice the input current, but the heat produced is massive. Extreme heat will lead to equipment damage/failure and there is no way to put a sufficient cooling fan on a small handheld flashlight. Cree recommends a 50% duty cycle when doubling the current, 10% duty cycle when tripling the current. Many of these lights may be claiming their maximum output based on the brightest millisecond during a 'strobe' or 'beacon' function which, by all means, is cheating as the average output of an entire cycle from flash to flash is MUCH less. Also cheating: all the Chinese bastards flat out lying about their flashlight's output. No matter the Cree XML LED, a constant output of 1600 lumens is beyond pushing the boundaries, will overheat quickly, and will eat batteries as that requires around 300% the rated input current. All claims of getting 2000 lumens or more from a single Cree XML LED are blatant lies. On eBay some people claim as much as 4500 lumens from a single Cree XML LED.