MidMark PowerAir Dental P21 P22 P32 Thomas Compressor Service Rebuild KIT # 77001636 Applies to Models: AOCRR42DQ, AOCRT22D AOCRT22DQ, AOCRS11 AOCRS12, AOCRT21Q, AOCRT21DQ, AOCRT22Q R22, R42, P21, P22, P32 (With Sierra Dental Eagle TruNorth Heads)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. Service Kit. Kit includes piston cups, cylinder sleeves, head O-rings, connector tube O-rings, cylinder O-rings, valves. DOES NOT fit the 2750 Thomas Models, Gast, or any other than those pictured.DOES NOT include the compressor head. 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!