Zurn RK34-975XL Wilkins Backflow Preventer Repair Kit For 3/4"  1", 1- Diaphragm, 2- O-Rings, cover, 1- #1 Check spring 2- Seal rings, 1- #2 Check spring, 1- Relief valve spring 1- Relief valve seal ring, 1- O-Ring, relief valve stem Size: 3/4" - 1"