Most pneumatic system components and air tools require oil lubrication for proper operation and long service life. Too little oil can cause excessive wear and premature failure. Too much oil is wasteful and can contaminate, particularly when carried over with the air exhaust. Pneumatic equipment can be lubricated by the use of an air line lubricator. Filtered and regulated air enters the lubricator and is mixed with oil in an aerosol mist. The air is then routed to the operating system.