Just received my predator x today, I put an 18650 in and when I turned it on it flashed quickly then turned off. The voltage on my battery was 3.7 volts so I'm not sure if the low voltage is the issue or if the light is DOA. Both of my 18650's are below 4 volts so I put them on an xtar vp1 to charge. I'm hoping the low battery is the issue and with fully charged ones the light will work. Has anybody turned one of these on with similar results? Any info would be great.