puzzle

I was changing a 14500 on an anglehead light of mine and found it wouldn’t work although freshly charged.
Very strange, because this batt worked ok in other lights, after a bit of head scratching and a closer inspection, I noticed that it seemed to be a bit shorter than the other batts.
So out came the calipers and I found that the body of this particular batt is 2mm shorter than the other 14500’s, 47.6mm compared to 49.8mm.
Anyone else come across this?. (trustfire flames)

Yes i just noticed this on a Nitecore D-10 that is very picky about battery length.. the fasttech vs the dx ones from years ago are different lengths .In most of my lights it's meaningless.