"This bomber-style leather aviation jacket has been lined with Kevlar to provide a minimal amount of protection."
The Leather and Kevlar Jacket offers slighty more protection than the common Flak Jacket and can be used until kevlar vests are found. It is not worth treating with Compound 18, as it is weaker than other armour. However, its main use would be to improve the armor for Edgar "Nails" Smorth, since he refuse to remove his jacket otherwise. Or, you could sell it to Kyle Lemmons for 10 thousand.