part 15853 O-Ring, Valve Plug Cat Pumps code 15853 Details Cat Pumps number15853 DescriptionO-Ring, Valve Plug Qty per pump6 or 15853 Also comes in 34151 Valve kit, NBR (STD)76251 Valve kit, NBR (STD) Fits these pumps Cat Pumps 35 Frame 3 35013507HS3517HS Cat Pumps 38 Frame block-style 2 3801HS3811HS Cat Pumps 68 Frame block-style 3 680168116821