+1 or 3x xhp70.2 
I’d rather get a single emitter + reflector version of the D4 or KR4 before any completely impractical versions.
Something like the D18 with a few XHP50s or 70s could be interesting though… Same with the K1 for a much higher quality competitor to the FT03 w/XHP50.2
I heard that a KR1 may be coming in several months.
A triple XHP50 will generate too much heat for this light, it can sustain output for a few seconds.
For a triple XHP50 you need a decent host with good thermal mass and heatsinking.
Exactly Yokiamy. why waste good leds in such a way. People seem to want gadgets that can peform for seconds. Like a party trick or top trumphs. To each their own ofcoarse but function for me is way more important.
Please don’t tease me like that.
As much as I like lots of lumens, 3x XHP50.2 in a single 18650/21700 EDC light just makes no sense. That's way over 100W it will throttle in what .. <5 seconds?
I’d be massively down for a KR1. I haven’t ended up getting a FW1A, so this’d make a great replacement and keep things a bit diverse.
I’m so temped to order the SST20 in 4K I can’t wait for the E21A version. I have no self control when I’m bored at home.
You got the will power! Hold back! Lol.
For what it’s worth, I’ve continued working on the thermal regulation. It has a tighter window now, a smaller range of temperatures it’ll accept… so it stays closer to the configured temperature. I also got it to adjust faster while still not overshooting or bouncing.
The runtime graph isn’t completely flat any more, but that’s probably a good thing. On a linear driver like this, it gets more efficient as the battery gets low, so it makes less heat, and then it naturally increases the brightness to maintain a steady temperature. This effect is fairly small though, and happens very slowly, so it’s not visible by eye.
I think the XHP50.2 yellow + green double tint is not pleasant to look.
E21 version is delayed without ETA.
The LED is from Japan, and now Janpan is also affected by the virus issue……….
Alright what bin is the SST20-4000k do you have in the KR4 Hank. 
It is not necessary to use the flashlight only in turbo modes. In weaker modes, the XHP50 will be more efficient and less hot than small XPL/SST… .
I hope Hank pay attention to the emitters XHP
You’d get similar results from a >4 emitter mule, with not a not much floodier beam profile and much better tint.
I was so looking forward to it! Have you decided witch CCTs of the E21 you will make available? I have tried the E21a in 4500K and I love it.
4500k or gtfo
As always, we offer various different CCTs if we decide to offer one type of LEDs, 2000, 3500K, 4500K, 5000K will be offered when they are available.
But there is no ETA yet since the Japan Nichia factory is locked down.