the k40 runs a lot cooler than the x60 on high o don’t know of that’s due to extra mass?
I would expect the K40M to run significantly cooler than the X60. MT-G2 even overdriven has to dissipate on the order of 35 watts, X60 has to dissipate on the order of 55 watts. There is a reason the X60 uses 6 batteries versus only 3 in the K40.
NIKOLAS,
before insulting others while espousing your remarkable level of ignorance in front of an entire forum, please try conducting a simple search and educating yourself next time. :Sp Then you may read THOUSANDS OF WORDS I POSTED ON BLF about my personal experiences of ownership, my communications with the manufacturer to tell them how to correct several of their engineering flaws and failed manufacturing processes, the many comments I made in support of others who were ripped off and lied to by them, and a large group buy for this brands flagship model that I conducted, only to find out what a massive bag of shitty failures and lies this company really is. Its all there for anyone who can read and comprehend English… all for the benefit of others, including you.
Also, there is insufficient room to mod the existing floor plate of the K60 to add sufficient material to conduct heat throughout the head. The addition of a copper adds very little if any additional ability to transfer heat. This is true of all the large sup/ace lights, which is why the emitter and driver cook the battery tubes, selector rings and batteries while the bezels remains comparatively cool. So in short, this is a VERY shitty design that could have been a real winner if the manufacturer had listen to its technical experts - the R&D members on this forum (3 of which have already chimed in).
IMO, anyone who spent a small fraction of time researching the products made by this company through the dozens of comments left by myself and others on this forum would never purchase anything from them ever again. Those who have been burned by them have made it abundantly clear of their disdain towards Acebeam for their blatant lack and denial of customer support and manufactured lies concerning several existing problems.
For those already stuck with failing K60’s and other acebeam lights, I wish you the best of luck. Please post your experiences in the appropriate threads and cross post to your own thread so search engines can guide others here before they make the same mistake of buying one of their lights.
Really? Looking back at your sharp tongued uneducated comment, your intent was certainly deliberate in trying to offend me… so lets cut the bullshit and grow up! You also proved that you did absolutely nothing to research or validate your false comments before posting. If you think its such a great buy, then put your money where your mouth is and buy one. 
A local rescue service purchased two K60 units without my prior knowledge. They turned out to be huge disappointments to the entire crew and leadership when they immediately discovered how useless the light became after 3 minutes. I was asked to drop by and see if anything could be done to improve the design and offer my suggestions.
I hereby personally validate the incontrovertible claims of others who quickly noticed how the selector ring overheats while the rest of the light remains relatively cool. Not only does it overheat very quickly, it overheats faster than my 5000 lumen X60, my 6500 lumen X60 and my K50 (all of which share the same poorly designed thermal path, or lack thereof). The light does not sufficiently transmit the heat from the narrow selector ring area to the large head surfaces, where the large head surfaces could have been used to exchange heat with the surrounding air if it had been properly designed. Not only did the selector ring burn my fingers in short order, the battery tube and cells within the carrier also became hot after a few intermittent 3 minute runs with 2-3 minute resting times in-between. This issue has been well documented by myself and others across all larger sup.acebeam lights. Probably no wonder the drivers fail because they are being roasted.
It was vinh that was the first to add copper to the X60 floor plate in a failed attempt to improve the thermal path, which drew our attention to the problem and perpetuated my repeated suggestions to acebeam to modify the design by adding sufficient material to transfer the heat throughout the head in future models… which they blatantly ignored once again in the K60!
I hope you’ll spend some time to read that facts before posting next time, because you’re assumptions have all been incorrect, distasteful and inflammatory. :Sp Also, there is a pretty damn good chance that without me, several acebeam flashlights may have detonated onto large fragmentation bombs and injured or killed people! Run along along now… you’ve got a lot of reading to catch up on!
tatasal,
This isnt a joke! Acebeam ripped off dozens of its customers with failed flashlight carriers! Go back and read the posts and try to help support those who were taken advantage of, otherwise take your STUPID childish troll comments somewhere else!
DO YOU UNDERSTAND?
Its a government conspiracy to flush out all the worthless bottom feeders who didnt do their research before posting… and its working far better than expected. The next thing you know, they might be able to reprogram your thought processes to actually think intelligently. Oh Snap!
Get lost kid, your diaper stinks and they’ve thrown you from the short bus.
I just cleaned up the recent nasty argument in this thread. Please drop the subject from now on. This is not an attempt to run a cover-up for Acebeam, but rather to keep peace on the forum.
For reference, please see FlashPilot’s warning at the beginning of this thread:
Again, I am requesting everyone to please drop the subject from now on.
I checked with my IMRs (Efest 3100 mAh IMR purple button top) till the flashlight blinks three times each 15/20 secs, on voltmeter the difference between batteries is 0,01 V (3,5…3,51…3,5) not even 0,02 V…
At 3,34V measured, the flashlight still work great at all levels.
To levels 5 and 6 after 2-3 min it blinks, this is a nice feature because you can run IMRs and the flashlight will announce you that the voltage is to low.
GREAT LIGHT
A small comparison between K60 and Nitecore MT40 (at full power 860 lm) , K60 at 700 lm the brightness is the same in my eyes (the spill is brighter), just that MT40 have a better throw, the tree at aprx 70-80 meters (~80 yards).
At 1700 lm nothing to compare, at 3500 lm only the spill make a lot of light at this distance 
Looks better now
Thank you Zeremefico.
Hope to make time for some photos at longer distance.
If Acebeam sales were warmer to us, K60 would be a must have model.
Waiting your beamshots…
I still like my K60 very much. :)
If you are a member of BLF and want to buy a K60, I may be able to help you to get one directly from Acebeam.
There might be some discount involved, but we can't discuss about it here or this channel will be closed. PM me for more details.
Forget about Acebeam, if you want one there is a better seller to get it from…
I still complaint about high frequency noise at level 4 (1700 lm) when the cells are fully loaded.
Close to my ear in total silent I can hear this noise - high frequence but not continuously/linear (it has some interruptions) but only when the cells are more than 4,0V and only at level 4 (some noise also at level 5, but not so much) .
WOH, killer deal. Get it before the MAP police take it down. The monster K60 blows the SD75 out of the water.
I’d get one if there was a bigger discount! Thanks for the info anyways. Cheers 
Thanks for the tip. I just ordered one for the 10% off. Best price I have seen.
Regarding the K60, I read in the specs the following:
”
K60 must use 4 x high drain unprotected 18650 cells, or protected 18650 cells which PCB including 3 MOSFETs.”
I know a mosfet to be a transistor, and I undestand their general function. However in this case, if I were to use the K60 light with PCB protected 18650 cells, how would one accomplish this?
Is this a common modification made to the flashlight driver?
If so, would there be enough room to add the transistors, and if so, where in the circuit would they be placed.
Any thoughts?
Art