During the everyday operation when you switch the modes and tighten / loosen flashlight parts, O-rings and threads undergo friction and wear out. That is why special thread grease was developed to maintain top conditions of the flashlight and prolong its life. The best choice for use with flashlights is thick silicone O-ring grease (thread grease) Nyogel 760G. This thread grease is very sluggish and doesn’t dissolve in most liquids as water, methanol etc. Besides it reserves these characteristics in wide temperature range.
 
The other reason to lubricate all threads and O-rings with silica thread grease is its water resistant characteristics. All Armytek flashlights are submersible up to 50 meters depth and can be used as lights for diving and spearfishing. Thread grease improves the water resistance of our flashlights and also enhances other features - eases mode switching and saves threads from wearing out. Flashlight grease can definitely prolong lifetime for threads in your device and provide your with better and most reliable performance.