My favorite AA light and my EDC is the Quark AA R5 with the "Regular" UI, but the "Tactical" UI is nice too. The regular UI is the type of UI where you cycle through the settings (head tight - max then strobe; head loose - moonlight, low, med, high, sos, then beacon.) I like this UI because it is a one-handed operation, and I leave it on head-loose most of the time. The tactical UI is good too and better for someone (like my wife) who prefers even more simplicity - high and low only. The tactical UI is programable meaning you program the two settings (head tight & head loose.) You have all the outputs levels to choose from - moonlight, low, med, high, max, strobe, sos, and beacon. But only two of these can be programmed into the light - one in the head tight position and one in the head loose position. Because of this UI you can turn the light on & off & on & off without cycling through any settings plus you get a forward clicky with this light allowing a "momentary on" feature.
What I like most about these lights is their versitility. The Quark AA can run on alkalines, lithiums, NiMh rechargeables, and my favorite a rechargeable Li-ion 14500 which bumps up the max output to 200 lumens with great runtimes...nice. Also, the head & tail can lego with the Quark AA2, Quark 123, and the Quark AA2 Turbo...great system. Because of the lego-ability you can change the light somewhat to suit your needs by buying accessories. I bought the "deep carry" pocket clip and a tactical tail for my Quark AA regular, and prefer the light this way. Another thing, the Quark AA is smaller & lighter than most lights (except zebralights) because 4sevens values small & lightweight (you can see this quality in most of their lights.)
The build quality is excellent, the customer service at 4sevens is an industry leader, and they remain on the cutting edge of technology with their lights. Check it out -
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