Nitecore DI o-ring size

Hey all, I'm having the same problem as many with my NDI. If I twist it "tight" it goes dead. But just a shade loose of tight and I'm in tactical mode. I'm going to buy some cleaner and lube this weekend and do all of that, but I've also read some people switch out the o-ring for a Fenix one. I don't have a spare Fenix o ring in that size, so I was wonder what size o-rings the NDI uses. And also, would it be better to buy the Surefire o-rings or the generic GITD ones from lighthound? If Surefire, which one?

Or I guess, other sources for good o-rings, doesn't have to be lighthound. Though I'd like to get my cleaner (Detoxit, right?), lube (Nyogel, still reading through the thread to decide which one. Does NDI need conductive gel?), and o-rings from the same place if possible. Thanks for all the help to a noob (I only have some Fenix AAAs and the NDI.)

Go to your local hardware (i.e. harbor frieght) store for o-rings. I bought a box of assorted size, very handy for various things.

jzmtl said:

Go to your local hardware (i.e. harbor frieght) store for o-rings. I bought a box of assorted size, very handy for various things.

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I had zero luck finding a P2D sized o-ring at Lowes, Home Depot, or Ace Hardware. They were all either too small, too big, or too thick.

I measured the oring on my P2D once with my digital caliper but it's kinda hard to measure such things..

Fenix P2D: 1.54mm thick, 18.4mm OD, 16.86mm ID

Khaytsus please take with the same method the measurements of the Defender's original o-ring.

Khaytsus said:

I had zero luck finding a P2D sized o-ring at Lowes, Home Depot, or Ace Hardware. They were all either too small, too big, or too thick.

I measured the oring on my P2D once with my digital caliper but it's kinda hard to measure such things..

Fenix P2D: 1.54mm thick, 18.4mm OD, 16.86mm ID

Click to expand...

Those store that sells individule rings like the one you listed usually doesn't have much in stock. I bought my big kit at princess auto, which is very similar to harbor freight in the states. Try that you'll probably have better luck.

Kilovolt said:

Khaytsus please take with the same method the measurements of the Defender's original o-ring.

Click to expand...

When I get it, I will. I'm hoping it's here by the end of the week!

jzmtl said:

Those store that sells individule rings like the one you listed usually doesn't have much in stock. I bought my big kit at princess auto, which is very similar to harbor freight in the states. Try that you'll probably have better luck.

Click to expand...

Good show. There is a Harbor Freight a few miles from my house, I'll have to check them out.

I have had luck with 2 thinner o rings,

1 from liteflux lf 3,it was thinner and a little to easy (almost) to turn.

2nd is an o ring from a mag 2AA mini mag head end.Twisting force is near perfect,still as water resistent as original. I did lube it with nyogel 759 G, from lighthound.

BTW mag light loved the nitecore oring,fit and twisting force is perfect.

Every one on cpf must have at least 1 mini mag to try!!:twothumbs