Park Tool

ASC-1 Anti-Seize 4oz Compound

This is a fine product at a good price. I use it on any threaded part that doesn't require lock-tite. Unlike grease, it won't wash out once the parts are threaded together, so it provides lasting protection to avoid thread seizing. A hint to use it without making a mess or wasting it, is to apply it with a small "plumber's brush" that you can get at any hardware or home improvement store.