So your saying the R51, R100, R100 combo coresponds to it being an 8A driver meaning it’s the one for the xpl’s.
The other driver with the R51, R330, R330, R330 combo corresponds to it being a 2.5A driver so that’s the one for the xhp35?
I was just going off the description in the first post; my understanding is that the TN42 was always XHP35, so yep the white driver for boost - but my reading off what Lexel has written is that the black one is for the TN42, or a TN40S that has been modified to run XHP35s.
But you’re right - for a definitive answer, only Lexel can really answer.
Thanks for the replies! 
Ideally, I’d do some bench testing, but as I mentioned I’m currently away from my tools.
I’ll wait for a definitive answer before proceeding. Thanks again!
I found a picture of a high amperage buck driver Lexel made and its using the same 3.3uH inductor. What driver do I need to run an XHP70 or 70.2? - #7 by Lexel
So maybe he uses the 100uH for the lower amperage drivers? (Correct)
The sense resistor bank is very similar between those two drivers with 0.025 and 0.035. So I don’t think thats a good indicator of which is which.
That’s all i can find. Nothing conclusive.
3.3uH is always a larger current -> same ripple voltage for regulation
10uH 2.5A, 3.3 4-7A, 2.2uH 7-8A
Resistor values the same the smaller the combined resistor is the higher the current has to be for same voltage drop
left driver 47mOhms*4.5A=214mV
right 90mOhms*2.5A=230mV
Thanks again to everyone trying to help identify my drivers.
Lexel messaged me and said the white one is for the TN42 (single XHP35) and the black one is for the TN40S (four XP-L HI).
I’m hoping to tackle the swaps this weekend. Both lights will need their battery carriers modified as well. I’m very excited to have Andúril in these two ThruNites.
Thanks again, Lexel! 
I have Endermans 2nd Syniosbeam with your CFT-90, 48 amp driver. I’d like to know the allowable maximum and minimum input Voltages. Instead of powering it with the current 3S LiIon internal and external packs, I’d like to power it with either a 3S or 4S LiFeP04 pack. my LiFeP04 cells are charged to 3.55 and always settle after charging to about 3.47 or about 13.88 pack Voltage. Is this within the allowable range? I’d guess a 3S pack might be too low - 10.41 down to 9.3 pack Voltage.
I’m looking for a couple of 22mm drivers for a M21C to drive a sbt90.2. Please let me know if and how I can purchase some?
.
You need to PM him for orders.
He may not check this thread often. 
Any other forms of contact…. FB, email, Instagram ect….
PM works fine. But he might not answer you at the moment because he’s busy with other things.
LM3409 basically changes switching frequency if input voltage changes, the driver is defigned for LiIon voltage sag
Making higher voltage with less voltage sag batteries is no good idea
Heat on the diode is also an issue
Do you have any 1S + e-switch driver tor 6V LEDs ?
1S would imply a 3 volt led.
Are you asking for a Boost driver?
Yep, I need a boost driver with an e-switch option.
I don’t believe he is offering any.
MTN Elec offers Boost drivers, but not with E-switch.
Convoy has one, its used in the m21c-u with an xhp70.2
I see a couple of boost drivers with e switch. One is 22mm.
Convoy flashlight Store
Pm sent
Just fyi for those posting/pm'ing to Lexel: he's had recent health issues, in the hospital I believe. He was back for a while, but he hasn't been on BLF in the last week or so. Hope all is well.