General Air Compressors are used in a variety of systems. This is a top end rebuild Kit for them. Having low air pressure is a sign of the internal wear parts need to be replaced. Service Kit. Kit includes piston cups, cylinder sleeves, head gaskets, cylinder O-rings, & valves only. Used in models OLRV12016AC, OLR55033AC-LP, and others similar to the one pictured.This is 1 kit to service & rebuild 1 Compressor Head only. Some systems have 2 or 3 compressor heads - in which case you would need to purchase 2 or 3 of these. DOES NOT include the compressor itself. Have a seized compressor? We have entire replacement compressors available as well! These are an aftermarket kit we manufacture to keep your equipment running like new. If you are having longer tank fill times, low pressure, low vacuum, etc. - your compressor needs to be rebuilt. Easily accomplished with common household tools and takes as little as 10 minutes.After rebuilding these can normally last up to 5,000 -8,000 hours.All items typically ship the same day or day after w/ tracking # uploaded (except weekends and holidays)We are a business and closed Weekends.We also have NEW Pumps in stock - ready to ship - Warranted - check out our store! We have kits for the Thomas 100, 2619, 2639, 2669, 2650, 2660, 2685, 2680, 2750, 1207, 405, 617, 668, 669, 927, 2807, T models ( 617, T-27,30, 30A, 25HD, T-50, T150, T-100/200, T2820, GAST ( most models ), etc.Thousands of kits available - Thousands of NEW Pumps available!