Quick view Add to Cart Replacement of Part 2315 Compensator Stem with Part 3198 and Packing 'O' Ring Part P-B1045-7 with Part MS28775-021 Document Part Number: Service Bulletin No. 50 Number of pages: 6Part Number: Service Bulletin No. 50Revision Date: 15-Jan-1958Description: Mfg By: NY Air Brake MSRP: Was: Now: $15.00