Mine cyan KR4 arrived today. Works great out of the box, the aux leds are pretty sweet. The way reds pop under the 3000k sst-20s is awesome. Just waiting on sundown to really put it to use!
Hank? any plans for some large overpowered flashlights this year? Maybe something even bigger than D18.
Any plans for a 21700 version of this light?
Interested as well!
I think the updated D1S with 21700 might be next?
The K1 is a level beyond the D1s. While very compact for it’s performance, it’s still significantly bigger than the D1s. Those larger machined parts are also going to mean higher cost:
Waiting on mine in the mail. In the meantime, will a longer protected 18350 cell fit?
Edit: was looking at the Keepower P1835C2. Should work fine since the cell is 35mm long but I am looking at others that are protected and are 39mm.
That’s factory reset mode. It’s what happens when the button is held while connecting power. If the body tube isn’t connected, it can still receive a little bit of power through the switch, which causes the behavior you described.
So it sounds like the parts aren’t threaded together correctly.
Ish. Not really. It can still activate factory reset mode while the tailcap is loose.
Yes, this light is meant to have the battery changed at the tail, not the head.
In the default configuration, the smooth ramp floor is 3/150 instead of 1/150. It can be configured lower, but could potentially be unstable on some devices because it’s outside the regulation chip’s supported operating specs. So the default is the lowest in-spec level, and it has the ability to go lower if desired.
A while back, the default behavior changed when turning on the light.
- Before: Press button, light turns on at moon. Release button, light goes to memorized mode. Or keep holding and the light gave a subtle blink to indicate it had been pressed long enough to be a “hold”.
- After: Press button, nothing happens. Release button, light goes to memorized mode. Or keep holding and when it has been pressed long enough to be a “hold”, the light comes on at moon.
This can be changed by flipping a compile-time option and reflashing the firmware.
Additionally, if the KR4’s moon level is at 1/150 instead of the default 3/150, it may take the driver a moment to turn the LEDs on. That’s because the lowest level is out of the regulator’s specified operating range. It technically shouldn’t work at all, but it does, so it was included as a non-default optional extra.
It may also help to set the floor to 2/150 instead of 1/150. This is the same level, in theory, but it runs the MCU twice as fast… and that extra power draw is just enough to make the regulator run slightly higher.
In any case, the lowest officially supported level is about 2 lm. But there’s an unsupported optional ~0.2 lm mode available for those who want to try it.
Thanks, TK. Well explained.
Noctigon K1, XHP35 HI version in stock.
Hank, any plans for a SBT90.2 version?
That’s great news Hank. What tint bin is used? Are these the high CRI versions? What output can we expect?
Tints are listed on the page: 3000K/4000K/5000K/6500K with corresponding throw #'s, but no exact bin info, CRI, lumens, or amps. Best guess is the driver is tweaked for ~2 amps to the LED, ~1,800 lumens. 2 amps to a XHP35 HI is a high draw on a single cell - at least 8 amps, maybe closer to 10?
It is 2A for the XHP35 HI LED.
Hi Hank. What would be the bin and cri?
I'm a good guesser 
I bought the floody optics with mine how do you get the stock optics out?
It should slide out once you remove the bezel.
Doesn’t seem to want to budge.