I don’t think you can really go wrong with any of them. I use the stuff Richard sells at Mountain. Only because I need a little jar of it every 2 years and he seems to have other stuff I need/want as well.
Question. Does the Nitecore stuff come in a really irritating blue tint? 
No, its clear. I just ordered two more jars from Battery junction at 2 dollars a jar. The screw on lid is nice and one lasted me over a year now. Running low so for 2 dollars a piece, that’s a great price. 8.86 with shipping for the two. Shipping was more then the silicone lol.
I have seen alot of recommendations on this topic, but general speaking most will say Nyogel 760G or Superlube.
I have used all the lubes mentioned in this thread and a few that are not and they all worked fine but I find I reach for the Nyogel more than any other for O-rings.
I use to use vasoline before all these exotic lubes came out. Worked fine but had a tendency to attract dirt. Now they say not to use vasoline because it deteriorates the rubber.
I have used vasoline on my rubber O-ring for my whole house water filter for 12 years, its still there and working fine.
I was being a complete smarta. I was just making fun of their mostly blue hued emitter choices. I’m sure their gel is just fine.
I like the screw on lid. Keeps everything inside instead of all over my little parts box. I use one of those really small brushes that women use for detailing their nails. Brushes on nicely. Don’t ask how I know more about nails than I care to admit.
:person_facepalming: Okay, now I get it 
I never thought about using a brush, what a great idea :+1:
I use the Nitecore grease.
Used vaseline before, then ordered some inexpensive silicon grease (unknown brand, AE or BG) which was too viscous for threads. Now I have a jar from Mountain Electronics which works great.
I bought a 3 ounce tube of Super Lube like 8 years ago, I barely made a dent in it, probably last me another 8 years, talk about getting your money’s worth
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Does anyone of you used these?
Cheap food-safe grade silicone grease. Works great to lubricate o-rings, not so much for threads because of the low viscosity.
I use Super Lube Multi-Purpose Synthetic Grease (that I got from Harbor Freight). Super Lube makes different types of greases so you have to be careful which one you use for flashlights.
The “Multi-Purpose Synthetic Grease” is compatible with both nitrile and silicone rubber, which I believe is the material used for the O-rings in flashlights. The black O-rings are usually nitrile and the clear and color O-rings are silicone.
But the Super Lube “Silicone Lubricating Grease” is not compatible with silicone rubber. Even the Super Lube “Silicone O-ring” grease is not compatible with silicone rubber.
That one is super in every aspect, price included. Bought one years ago at FastTech, from this $2.61 listing; they also have it listed at $3.15, guess they messed up.
Am I the odd one who use Permatex Dielectric Grease on my lights?
Superlube has worked wonderfully for me and is available locally
.
I will give it a try, my lights are dry and need lube. 
I use RICO Cork Grease, it`s for clarinets and saxaphones etc… it comes in a tube just like chapstick and works great!
i bought some silicone lube at a dive shop prbly 10 years ago, i figured if it was good for divers, it is good enough for flashlights.
Well if you had some laying around then go ahead. I would still go with any form of silicone lube over dielectric grease.
I find that dielectric grease is sticky that’s why I use them especially on my keychain twisties. As for any different from silicone lube, I think it’s more economical to use silicone lube plus it moisturizes your o-rings
I use the Ford Motorcraft XG12 dielectric grease thats Nyogel 760G. Good lubricant for O rings and threads? - #19 by RobertB
Not sure what the permatrex makeup is but it could be close to the same.
The XG12 was much cheaper than buying the retail labeled 760G grease.
It was sold on BLF at one time. SOLD OUT! -- thank you -- 3 ounces of Nyogel 760G for $12, postage included -- U.S. only