This zipper lube is a useful product. I have a pair of old but good leather jackets with greenish copper on the brass zippers. As a result, her work was difficult. I applied a small amount of this lube to a couple of cotton swabs and ran them up and down either side of each zipper until all parts of the zipper were clean. The dirt is gone and the grease has replaced it so the zippers now look and work much better. Advice. When using this lube on clothing, gently apply a minimal amount of lube and then gently rub across the zipper to prevent the lube from migrating elsewhere. (Not that it could do any harm if it spreads a bit.) Follow up. The copper zipper on my wife's purse was stuck. So I applied a small amount of this lube to the zipper teeth in three or four spots and then ran it up and down the zipper a few times to distribute the lube. Easily erased the excess and everything worked!