Newbie question on Dereelight NM400 and batteries


Newly Enlightened
Aug 31, 2012
I've bought a Dereelight NM400, led is XR-E with 2MT-M driver.

It's a good led? How it is compared to XP-G2 and XP-E2?

About batteries, should I use a single 18650 or two 18350 (I've seen that in other Dereelight the description states: 2MT-M single 18650 works but can't get full power)? If choosing the 18350, better rechargeables or primaries (CR123)?

Sorry for so many questions but i've searched the forum and I'm more confused than before the search. Thanks a lot in advance for any help. :twothumbs


Flashlight Enthusiast
Oct 11, 2013
Hengelo, NL
Okay, I'll bite... ;)

a) XR-E efficiency/output varies a lot depending on bin, see Cree XR-E datasheet & specs for your light. Can you find anything concerning the XR-E bin used in your NM400 ? Generally speaking the XR-E is okay. Not the best out there, but you could do a lot worse. :)

b) Unless you absolutely need it for the voltage, using a single 18650 is much preferable over 2x RCR123's in series. Much higher capacity & no multi-cell issues. If you 'must' use 2 smaller cells in series, I'd go for unused & same brand/batch CR123A primaries.