That seems disappointing.
He’s saying the switch is much better and less prone to accidental activations Like the FW series. How is that disappointing?
Some more observations:
- Tailcap lockout: The KR4 has true tailcap lockout. A quarter-turn is enough to completely disconnect power from the driver. This is different from the FW3 series where partially unscrewing the head or tail only disconnects the switch while leaving the driver powered.
- Loose pocket carry: So far, I’m quite liking this light. I removed the clip and am now carrying it loose in my pocket. The fluted body shape feels much better in the hand than an FW3A, and between the flat knurling and grippier anodizing it feels much more secure in the hand when held in a handshake grip, while being about the same with a cigar grip. No accidental pocket activation yet, but that doesn’t prove a lot.
- Output: It’s as bright as the Emisar D4 and brighter than an FW3A. It also seems to manage heat better than either. It seems able to maintain high brightness longer than either the D4 or FW3 series.
- Moonlight mode: at least on my sample, minimum brightness is more of a “very low”. It’s not quite as dim as the moonlight mode on my D4 and FW3 series lights. I assume this is due to the constant current driver. I consider “moonlight” to be dim enough you can stare directly into the emitters from close range. The KR4’s dimmest setting seems just outside that range.
- Clip o-ring - In the FW3A if you remove the tailcap the clip pops up and the little o-ring above it tends to fall out of position. The purpose of that o-ring is to prevent the clip from spinning when the light is sealed. In the KR4, that o-ring has its own slot. In addition to preventing the clip spinning, it also securely retains the clip in position. When you take the tailcap off to change the battery, the clip and its o-ring stay in position.
Oh, that’s a shame. My D4 is just within that range where I can stare directly at it.
Is the ramp floor set to 1/150?
Appreciate the posts on your KR4. Looking forward to mine. Ordered the 3000k, hope the tint is decent.
When you remove the pocket clip, please do not forget there is lanyard ring which can also be installed and try.
Good point. The light comes stock with a lanyard ring that can be used instead of the pocket clip. It also comes with a lanyard.
He also said it wasn’t a huge amount more resistant and that it is less resistant than the FW3A with the o-ring mod. I was hoping for a bigger difference.
Those are incredible! I already have 2 D4V2 Ti but I ordered the Blue Swirls, including 18350 tube, with SST20 3000K. Can you please verify these LEDs are of a below the BBL tint?
Unless it changed recently, Hank’s SST-20 3000K is HB4 bin, above BBL. You could use a Zircon filter to remove some of the yellow/green.
Would you be interested in SST-20 2700K JA3 bin, below BBL? You could try emailing Hank, maybe he still has some left.
I just noticed, Blue Swirls are gone 
Thank you lightdecay. My light was shipped today. I really hope it has below bbl tint or I will definitely have to reflow some other LEDs.
Hank, do you know what tint are my SST20 LEDs?
He ordered SST-20 3000K. Still HB4? Any chance of HD2 bin in the near future?
I thought it was FA3 only the last time I asked. So you ordered a FD2 batch also? Please only use FA3 because it is noticeably less yellow/green than the FD2. Of course if you can get FA1, FA4, FD1, FD4 bin would be even better. 
I ordered SSTSST-20 3000K indeed.
FD2 is right beside FA3 the difference is 125K, it is very little, it is neither above BBL and neither a thousands of Kelvin distance, to be more “yellow” and “green”
What size trits for the KR4?