Ultra-Pure Linkage, Lever and Key Oil is used for rotary valve mechanical linkages, ball joints, levers, keys, triggers, etc. It is excellent on all threaded parts, such as valve cap threads and threaded bells. Use also as woodwind key oil for clarinet, saxophone, flute, oboe, bassoon, etc. Since it is a thicker oil, it will last a very long time and will protect metal-to-metal joints.