1) O Ring Hp Cylinder For Knorr-Bremse Compressor Of Wap4 Locomotives To Kbi Part No: Orc1180000. 2) O Ring Lp Cylinder For Knorr-Bremse Compressor Of Wap4 Locomotives To Kbi Part No: 469057. 3) O Ring Hp Valve For Knorr-Bremse Compressor Of Wap4 Locomotives To Kbi Part No: C160077/10. 4) O Ring Lp Valve For Knorr-Bremse Compressor Of Wap4 Locomotives To Kbi Part No: C160077/5.