These zinc plated flange kits (also available in Stainless, suffix SS) consist of two flange halves, four bolts, and a nitrile O-ring (replacement O-rings are in the Hydraulic Adapters section), and are used in conjunction with either flanged hose ends or with flanged adapters. They are available in both Code 61 (i.e. 3000 psi) or Code 62 (i.e. 6000 psi). Code 61 and Code 62 do not interchange (the Code 62 is a thicker, heavier pattern), but they do use the same O-ring. Tighten bolts in an even fashion and do not over-torque (contact us for torque ratings).