Operating your Quark 123² is simple. Make sure its batteries are inserted with the positive side (+) toward the head. Ensure the bezel (the 'head' of the light) and tailcap are tightened, then depress the tailcap button fully so that it 'clicks' and the light turns on. The two most commonly used modes are Max and Moonlight, the highest and lowest modes. To access Max, you simply tighten the bezel. To access Moonlight, you just loosen the bezel a half-turn. That's it. Give it a try now by cycling back and forth between Max and Moonlight. You can also cycle through the Quark's other modes just as easily. Lightly depress the button momentarily (you don't need to 'click' it off) and the output will switch to the next mode. The mode sequence is determined by whether the bezel is tightened or loosened: Loosened Bezel: Moonlight -> Low -> Medium -> High -> SOS -> Beacon Tightened Bezel: Max -> Strobe Once the Quark has been turned off for at least three seconds, it will revert to the first level of output in the sequence, either Moonlight or Max.

Power: Two CR123A Batteries (3.0V~9.0V)

Output: Maximum - 190 lumens; Moonlight - 0.2 lumens

Runtime: Maximum - 1.8 hours; Moonlight - 30 days

Strobe: Strobe, S.O.S., and Beacon flash modes

Length: 4.5 inches Diameter: 0.86 inches Weight: 1.8 ounces