They are legit. This one that I have on my BCM 11.5" is the smaller, lighter 350 lumen version. Amazon had the bundle with the light and the Arisaka inline MLOK mount for $115 which I felt was a good deal considering the mount is $37 by itself. It came programmed as #allthelumens on the first click, strobe if you click twice, low on the third click, constant on with the button, which also allows you to bump fire it into the mode you want.
I don't have a ton of rounds with it mounted yet, probably 500 or so, but so far so good with no flickering. Prior to having the BRT Covert Comp on this gun, I was using that Vltor flash hider in the picture. After one range trip, it was caked with carbon as to be expected, but it cleaned off much easier than other weapon lights I've used. Not sure if they coat the lens with something but it sure made wiping off the carbon easier. I'm gonna order that 1000 lumen model as well.
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