One seller: http://www.lightmalls.com/trustfire-x100-7xt6-7-cree-xm-l-t6-high-brightness-8000lm-5-modes-led-flashlight-4x26650
And another: http://www.iaminthestore.com/trustfire-x100-7t6-7xcree-xm-l-t6-high-brightness-to-8000-lumen-5-modes-led-flashlight-with-gun-package-and-strap-4x26650
Because it’s severely underdriving the LEDs. At 7 LEDs you would like to see 14 amps or more, 2A per LED, hell, even 10.5 for 1.5A per LED would be better, but at 7.5 for 7 LEDs you’re giving each just a little over an amp, almost pointless.
Oh yeah, I missed that, thanks. I thought the 7.5 A was battery current but I see now that it's "regulated" 7.5 A so it must be the LED current. Gee, if that 7.5 A figure is true, it's only pushing about 25 W into the LEDs. Some of the 3x XM-L lights are doing 30 W or more already, so what would be the point in manufacturing this huge light driven at only 25 W?
I hope the 7.5 is a typo. Or, if the 7.5 A turns out to be the battery current, now we're talking...
7.5 A x 4 x 3.5 V (approx. battery voltage under load) = 105 W
driver efficiency = 80% approx. ==> 84 W reaching LEDs.
12 W per LED ==> about 3.5 A per LED. That would be awesome but the light would get stinkin' hot, fast.