Lithium waterproof grease
How to lubricate entry doors and what to use : Lithium Waterproof Grease
Quote from Article entitled How to lubricate entry doors and what to use:
The whole procedure of cleaning and oiling is rather simple. First of all, you should put a lot of cleaning substance into the lock barrel, insert a key in the lock, and then immediately remove it. Afterwards, wipe the key and repeat the procedure once again. Keep doing it, until the surface of the key stays clean. The process of oiling the locking-mechanism is just the same. You should open and close the lock a few times, so that the lubricant spreads and dispenses.
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