Looks pretty good. Some of the adapters out there are way too loose. Those look like they probably wouldn't slide and rattle when the cells are under spring pressure. Thank you for the pics. 
I was going to say that (“wouldn’t slide and rattle when the cells are under spring pressure”), but didn’t want voice the opinion :).
I just tried that same battery+tube in one of my Defiant 3AAAs, and it’s ok. If I shake the light “violently”, I can “feel” some “thudding”, but no sliding or audible “rattling”.
Then again, the springs on the Defiant 3AAA is pretty weak, as you probably know :)…
You shook one of your lights violently? I'm turning you in to FPS (aka Flashlight Protective Services). Haven't you ever heard of Shaken Flashlight Syndrome? You should be ashamed of yourself.
One cell has been discharge tested after its first charge. Came in at 1655mAh. Looking good. Thank you Gj for reporting these!
I don’t understand how you all are getting these so fast. I ordered on 10/3, and they still aren’t here (in VA). Maybe it’s because I also bought one of the 12-cell packs?
EDIT: The “violent” shaking was on your behalf, so I should be ok, right?
For little ole me? I'm touched. At least that's what others say.
I discharge tested another cell after its initial charge. This one was 2 volts out of the pack. Discharged at 1 amp down to 3 volts resulted in 1697 mAh. Can't complain about that. Discharged it further down to 2.5 volts, but only got an additional 11 mAh's.
I forgot to say above that the first cell I tested came out the the pack at 2.2 volts. Discharge test above was also 1 amp down to 3 volts.
I’ve had good success cutting a piece of 3/4” copper water pipe for an adapter. The primary light these will get used in has this full length, to help control heat and I also like the heft of it with the copper in there. 
Edit: This is a TechLite Lumen Master, supposedly a light that dies in short order. My son has played with this one for almost 3 years, he just turned 6 end of August. The anodizing is getting worn off, it’s had a hard life, and it works just fine.
I think you can use irrigation pipe, too. I bought some at Ace Hardware but haven't gotten around to cutting it yet. It's too large in diameter as is but I plan to cut to length, then slit lengthwise removing enough material to compress fit. I forget offhand, was like 40 cents a foot, cut to length so you don't have to buy more than a foot. Has a bit of curvature to it but I don't think it'll be a problem in such short lengths.
And more good news. Decided to measure how much of a charge the last cell I discharged took. It took 1,797 mAh at 1.8 amps. That it twice the capacity of 3 AAA Eneloops. So here are some benefits of these cells on 3 AAA lights:
- Twice the capacity
- 6 less connection points (less resistance)
- 3 less springs (less resistance)
- Less cells to fiddle with and charge, etc
- Frees up AAA's and 14500's for other lights and devices
- They look cool
I have already put all 6 in lights. I still need to mod the Rook to take them.
Nice ideas DBCstm and Gj. I will probably use both approaches. The copper seems like a great idea for thin lights that need more mass.
Another benefit, 1 of these is cheaper than 3 Eneloops.
Late to the party! I have 3 of the 3 AAA carrier lights that sit unused. Then I noticed this thread and ordered a pack. They should be here Friday so will run a couple through my hobby charger. Good one Gj.
i just got one more from the same seller, i cracked it earlier got 4 measured at 3.2 and 2 measured at 2.1 , kinda odds.
That is odd.
Mine arrived today, all six cells were between 2.1 and 2.2 volts. I was a little disappointed at the low voltage. All six were charged at 1A with no abnormal heating. They came off the charger at 4.19 volts.
My hobby charger has a 0.1 volt error on discharge so it stops when the cell is at 3.1 and not 3.0 volts like the program indicates. The first one was discharged at 1 A to 3.1 volts with 1612 mAh.
These will be used in a SureFire 9P bored to fit 18 mm cells. I would have preferred protected cells for series use but at $1.50 each I guess I can’t complain.
I also put one in my free Harbor Freight 9 led triple AAA light.
Edit: All six tested between 1612 and 1658 mAh.
Still a great deal & great experience - Ordered very early Thurs AM, shipped later that day, arrived Saturday - ahead of Monday scheduled delivery!
Same experience as OP, save for slightly lower voltages. Assuming mine hold charge well I’ll probably order a 2nd pack these all have already found a home, kicking the last of our AAA flashlight alkalines to the bin - plus cheaper than 3 ’loops.
Nice to see the price did not jump up as did the 18650s.
The first pack all charged perfect at 4.2 with capacity around 1650 or so.
Yes, Harbor Freight and most of the 3 and 4AAA Utilitech lights at Lowes with sleeves. I’m running the 4 AAA at 2 amps(DD) with the 18500.
Just ordered one of these…$1.50 ea. for Sanyo 18500s is a great deal…Thanks!!
nice find.i loaded up on em.makes those stupid 3aaa disposable things worth using.wrap in a layer of thin cardboard to control rattle.
I got mine in…that was the easiest cracking I’ve ever done! It felt like cheating!
Thanks Gj…this will be filed under “Things you would never know unless you hang out on BLF!” :party:
I have the pictured Utilitech light (3xAAA) post #54, and with some’1800 mAh’ Trustfires, I really get some great output… measured ~1.6mA. So I figured if I use these Sanyo 18500s, it would be amazing! Well, yes, the output is amazing but, for the first time, I witnessed the dimming that happens when an LED gets to much current. I was measuring 3A for the poor XP-G.
I’ve also had a glimpse of the lowest voltage a Li-ion may be ‘recovered’ from. Of the 3 pairs in this Toshiba pack, 2 cells were at 1.9V and when I first put the two in my Nitecore I2 charger, the indicator lights showed fully charged with in a few moments. So, I thought four out of six isn’t too bad for $8.99, but… I started the charging sequence again and this time, they charged as healthy cells. BTW, it took about four hours to charge each pair from between 1.9V and 2.2V. They charged to 4.21V-4.23V. After 24 hours, they are holding their voltage.
With some of these adapters , I have plenty of high-current capable back-ups for my M2, S6 and other 18650 lights. The height of and half of the width of a box of Kraft macaroni provides the right amount of fill for my 3xAAA lights to fit 18500s.
This is a great find… the question is, just how many backup cells do I really need?
Thank you Gj and BLF
If the voltage is below a certain value, the i2 will decide it's a NiMH and decide it's fully charged.