Awesome review Maukka!
Any idea when the E21 emitter version will be available for sale? If it’s going to be soonish, will wait and get both the K1 SBT90.2 and KR4 E21 at the same time.
Also, on the intl-outdoor site’s search bar if you type in D1S, there’s an interesting suggested autocomplete for “37D1S v2”. Sure would like to see that come out soon.
Our E21A LED package is stuck on the way for long time due to the virus issue, not sure when it will move, so, we are not sure when it can be offered. The 10623 optic will be default optic for the KR4 E21A version.
IMO pretty mediocre tint but that was to be expected for a D240 binned E21A. The D220 4500K should be much rosier.
Thanks for the review. Very useful graphs as usual! The driver looks really good.
Mine will hopefully be here tomorrow. I need to get some 18350 cells, has anyone verified the max length yet? I would like to get a protected cell to avoid over-discharging if I forget to not use turbo. Assuming turbo for the xpl version draws more than an 18350 can handle.
Hard pass. CRI99 or else 
CRI99? … sounds like you want an old incandescent maglite!!! :sunglasses:
Reminds me of the old incan Solitaire. Max output was 2 lumens (though I think even that was optimistic), and the light was zoomable with 2 modes:
- “Spot mode” - this put a small dim spot of orange light. Sufficient for illuminating something 3 feet away, such as the keyhole of a door.
- “Donut mode” - this created a thin orange donut-shaped ring of light. Very dim. Not useful for anything.
which emitter?
I ordered the 5000K xpl. So it should be nice and bright but still neutral.
Using turbo doesn’t somehow disable the light’s built-in LVP. There might be protected 18650s that could handle the drain from a D4 on high or turbo… but they will be rare and probably expensive. No protected 18350 will be able to handle the higher output levels without tripping the protection circuit.
I’m not even sure most protected cells will fit a D4. For kicks I checked if a Wowtac 26650 (flat top, protected) would fit my D4S and it was too long (wasn’t going to risk crushing something by forcing it).
Sorry, that is what I meant originally, current draw. I would rather have the cell protection trip and be annoying than damage an unprotected cell. If I can’t find one that could handle the current without damage.
18650 Battery Store has a Samsung 30Q with a 15A protection circuit. Still would not fit because it is listed at 68.64mm, which is a bit too long. I know you were talking about an 18350 but I haven’t seen many protected batteries be able to handle higher current.
I will just have to be careful then, thanks!
I’ve noticed that most optics that have data from Carclo/Khatod/Ledil or whomever, always seem to have unfavorable results with the E series nichias. I wonder how much of this has to do with them being so thin and domeless, resulting in them sitting too far below the optics? Has anyone tried drilling (counter-boring) the mcpcb holes to see how the optical efficiency and beam change with a different focus?
I wonder if they made the KR4 with a buck driver if the efficiency would go up substantially.
This light looks like a great alternative to the FW4A. Anduril software is fantastic.
Are there sources to order these from in the USA, or only from China?
Is Intl-Outdoor a good source for these?
I can vouch for Intl-Outdoor, placed many orders and never had a problem.
It’s Hanks own store so fully legit and you will be looked after.
Thank you, x-ray! Good to know. I will order from Hank.
Looks very nice, but a little pricey.