I’ve been running it for a time now and I can attest that it works much much better on 2xRCR than it does on a single li-ion power source.
To date I’ve run it on an EagleTac 3100mAh 18650 and an IOS 18650, AW RCR (x1 and x2) and Trustfire flames 14500 (x1 and x2).
With the 18650’s its ok will a full charge, but dims significantly from around 3.9v, oddly more so than my non regulated Crelant V9CS does using the same cell.
However on 2x14500 or 2xRCR its actually rather a good drop in and seems to be performing very well. I would also argue (although can’t measure) that it appear to put more lumens as PEAK running this battery config as well as much more stable output. It does however run hotter.
I always look at the official specs which are pretty accurate
Specifications and Features :
Module consists of a CREE XLamp XM-L LED and an aluminum reflector
Outer diameter of reflector: 26.5mm
Single, 3 or five modes output
Maximum output up to 550 lumens
Model available (Luminous flux level, mode available, input voltage):
LC-XML (U2,Single mode,2.7 - 9V)
LC-XML (U2,3 modes,2.7 - 9V)
LC-XML (U2,5 modes,2.7 - 9V)
Lumen and runtime
One 18650 at high: 500 lumens, 2 hrs
One 18650 at medium: 225 lumens, 4 hrs
One 18650 at low: 30 lumens, 35 hrs
Two 18650 at high: 550 lumens, 165 mins
Two 18650 at medium: 270 lumens, 5 hrs
Two 18650 at low: 58 lumens, 30 hrs