What size HDS legacy O ring?

I have an old HDS 17670 tube (legacy V threads) from when Lighthound (a moment of silence please...) was blowing them out. Running a Novatac 120T with it and tore one of the O rings. HDS has a ring "kit" for 5 bucks, but I just want to buy a handful of them. Too thin for the plumbing section at the hardware store ( thinner than the ones on my Novatac CR123 bodies) anybody know the actual size? Any aftermarket replacement recommendations?

Of course, you might try emailing Henry. But reading his legacy user manuals reveals some discrepancies.

The manual for my EDC basic states in the cleaning & maintenance section that the standard battery compartment O-ring is:
"1mm X 22mm, 70 durometer Nitrile (Buna-N)"

but the same section for Novatacs states:
"1.5mm X 21.5mm 70 durometer Nitrile (Buna-N)"

So, not sure what these battery tubes actually use. I also have one of these closeouts, and took off the tailswitch to put on my EDC Basic 42. When I get home, I'll try to remember to measure the rings.

Update:
I measured the o-ring on my 17670 tube, and it's 1.05mm thick. The groove in the tube is 22.5 dia. so I believe the 1x22mm is the correct size for this setup. Also, my spare o-rings from Lighthound say 1x22mm.

Curious about the Novatac spec o-rings, and whether that has implications when using HDS parts with Novatac. I don't have any Novatac.

Louie,

Thanks for the great info! I did send an email out to HDS asking about it.

The O-ring is extremely thin. 1mm sounds about right, I should have checked the remaining one with my calipers to see if it was in the ballpark. It is much thinner than the corresponding rings on my Novatacs, none of them will work with that tube.

You bring up a good point about the implications of mixing parts, but I think in this case there's still a good seal.

If Novatac rings are 1.5mm, that would explain that. I have had 1mm HDS rings distort when installing the battery tube and get bunched up. Maybe Henry realized this, and changed Novatacs to 1.5mm and smaller diameter.

I found 1x22mm nitrile O-rings online and ordered a bunch. Thanks for adding the durometer number, I got 70's. We'll see how they fit when I get 'em.

Got a response from Henry. Oddly enough, he said it's 1.5mm x 21.5mm. Doesn't seem to jive with your measurements or what I've experienced trying to swap the rings around, but if anybody would know it would be him.

Still, I'm going to remain confident and see how the 1x22 rings fit when I get them.

Let us know! And if you recommend the O-ring vendor.

Came in yesterday, works perfectly. 1mm x 22mm is right on the money for this application. Thanks for looking up the actual size and durometer.

Oddly enough, there's a site called "The O-ring Store". Quick and easy ordering. Came in a few days. Of course, shipping is many times the cost of the o-rings, but you can buy as many as you want. I think the minimum was like 3 or something.