Umbrella Corporation AeroShell 33MS / 64 Gun Grease .5oz / Mil-Spec for Barrel Nut Thread MIL-G-21164D for upper receiver threads, barrel nut installation and buffer tube installation High quality lube good for any number of applications, exercise equipment, hinges, reels, ball bearings, bicycle gears, even telescope mounts Aeroshell 64 / Aeroshell 33 MS sets the standard with exceptional anti-corrosion and anti-wear performance Our portable .88oz jar (.5oz grease) container makes for easy application of this AR grease with just the tip of your pinky finger Made to perform under extreme pressure and heat to prevent damage.