I have one with green only and one other board with blue only.
so far none is mounted, as I am trying to get anduril compiled with aux enabled 
love the d4. switched mine from LH351D to Sst20 today. double the throw with just a minor dip in output. both 4000k high cri
switching over to sst20 sounds tempting . . . . .
It’s worth it, you get some decent throw and high CRI at the same time
only if you did not have high cri before. Both 219b/c as well as LH351D are available as high cri. I only use high cri for edc lights and headlamps
but the added throw is nice
Well I own quite a few lights and some decent emitters already (219A/B/C in different taste, LH351B/D and some 3000K/4000K SST20…) and the SST20 are a really good compromise.
My D4 has 2*3000K and 2* 4000K and is my EDC for the winter.
I have two emitters XP-L HI V2 3A and two 5D. Not sure what the CRI of them are but I like the light they produce.
Can anyone explain the difference between 219s and the LH351s? Are the Samsung LEDs more efficient?
there are different Samsungs. LH351C and D. D has bigger die like XPL.
they are more efficient. But 219b high cri has the best tint + color imho.
sst20 is nice as well, but the 4000k high cri is no match in tint and color quality to 219b
1. The LH351D 90CRI is the most efficient high CRI LED, but is more geared towards flood.
2. The 219Cs are the easiest LEDs to find.
3. The 219Bs have the rosiest tint and equal color rendition. It doesn’t actually reproduce the colors the most accurately though, and is the least efficient LED here.
4. The SST-20 is the throwiest high CRI emitter, has better color rendering than the 219C and LH351D, and is the most accurate emitter in terms of color rendition.
In fact, if it had a rosy tint like the 219B, the 219B would immediately be obsolete. It looks excellent regardless, but most people here prefer rosy tints rather than pure white tints, or very slightly green.
SUCCESS!
My Emisar now runs Anduril with enabled Aux for D4. Also Blinkies have been reduced to candle + lightning storm
Thanks for the tips pointing me in the right direction.
Grats! Hoping to do something with my D4.
I’ve ordered aux led boards from Lexel. Looking forward to installing them in my D4 lights when they arrive.
Hit a snag with Anduril flashing, but hope to have it ironed out and working soon.
:partying_face: 
:+1: 
Nice work! what sort of control do you have over the Aux board? While I don’t like some blinkies, I do find the bike light blinky very handy at times. I would go for that, candle and lightning.
You can activate and deactivate the aux LEDs and you can also set them to beacon mode. The beacon timing can be configured before compiling the firmware, as well as which blinky modes you want to have (and anything else actually :D)
Pöbel I assume you patched out the parts of the code for the blinkies that you dind’t want. The strobes do not run at 100% power in Anduril am I right?
EDIT: I read the code briefly and indeed: “” full FET strobe can be a bit much… use max regulated level instead,” (Anduril code)” ;_;
Some nice work on the D4 lights going on 
Crosspost from the “what did you mod today” for future reference
Tailcap in the lathe —> 15mm hole —> glued magnet (15*3mm) —> strongest magnetic attachment in my collection
Have photo of inside the tail cap?
Much nicer than my magnet job 
The inside looks stock, in fact the tail is 3mm thick so the magnet is flush to both sides (inside and outside).
