http://www.aerotechdesigns.com/whitelightninglube.htm

There was so much dust at the Santa Cruz Flats Race that it was imperative that pilots do everything to keep their harness zippers clean and lubricates. The dust would just eat up the zippers.

I was using silicone lubricants and cleaning the zipper after every flight. One suggestion was candle wax. I bought a cheap candle and have been rubbing the zipper ever since with it. It seems to work great. I wonder if this bicycle lubricant (which I use on my bikes, and like very much) would be a good idea. I don't want it to get on the harness itself.

I've placed it on the zipper of my harness. It's easy to keep off the harness itself. We'll see how it works.