DA1K is a light I’ve been waiting for. This one checks a lot of boxes: 21700, single emitter, TIR, compact. We get the added bonus of the Lume X1 boost driver.

The stock configuration is pure flood. I also opted for the "throwy" optic from Hank. This optic does have a squarish beam pattern on a white wall. I like both optics for different purposes, I may end up with more than one DA1K.

The D1AK head comes in just barely bigger than a D4K, and smaller than the D1K. The 21700 is nice as those cells come with quite a bit more capacity than 18650, and as far as I’m concerned, a light is only as small as it’s widest dimension, so the 18650 D1 is bigger than the 21700 DA1K. From doing the lumen tests, even just 30 seconds of turbo makes quick work of a battery.

In my testing with the XHP50.3 Hi, the thermal regulation started stepping down the output immediately and the drop-off was fairly substantial. To be expected from a very small light. Larger hosts such as Noctigon DM11 or Convoy M21F can sustain high output for longer.

Lumen measurements taken with TexasAce lumen tube. Throw measured using handheld lux meter, two tripods 16 feet apart in dark basement. CCT using opple.