51-385311208: Fits JW series vacuum generator (VG4) and M series vacuum pump. One kit includes two 2" duckbill valves. Two sets are required for complete valve replacement in a vacuum generator or vacuum pump. 2 per pack

51-385310076: Contains two 1-1/2" rubber duckbill check valves for VacuFlush vacuum and discharge pumps. Fits pump models: S12DM, S12DAB, S24D, S32D, S115A, S12, S24, S32, T12, T24, T32, VG12, VG24, & VHT. (All S and VG pumps require four duckbill valves). 2 per pack