... Detail introduction followed as below Feature of FK series combinatory valve blocks as belows:Model FKA,FKB,FKC,FKD,FKE,crossover ... model FKS cushion crossover anticavitation relief valves.Being a combinatory valve, it can bolt directly to the port face of ... and inlet check valve prevents reversed flow load circuit,a relief valve is the protection of the pump. FK series combinatory valve blocks