This is our rebuild kit for the automatic fuel shut-off assembly. Deere provided these assemblies as an oil pressure activated shut-off and sediment filter for their number series tractors. They could also be retro fitted to the earlier letter series with some plumbing into the tractor oil /lubrication system. These assemblies were of die cast material and their operating parts were of material suitable at the time. With the introduction of oxygenated fuels (ethanol), these materials suffered from attack and premature failure by the new fuel blends. Various compounds have been used using BunaN rubber, Fairprene, etc. These materials are better, but still not a suitable replacement. We use a Viton compound correctly formulated for ethanol based fuel. It is currently the best material to be used where ethanol may be present. We then look at the other components of this assembly. The original screen was a plastic/nylon material which positioned in place in the double lip of the glass sediment bowl. We choose a stainless steel replacement screen. This is impervious to chemical or UV degradation. This screen is pushed into place where the unhemmed center ID grips the housing. The valve is installed and our Viton bowl gasket is installed sealing the OD of the unhemmed screen. This Viton gasket is reusable when servicing, unlike the cork/rubber blended gaskets used by everyone else. We complete your assembly with 6 stainless steel fillister headed screws and lock washers. No one offers a more complete kit. We also carry other parts for this assembly that are not normally replaced, or may be missing. The kit listed here will fit your gas 720/730 tractor. Why is there so much emphasis on the materials used here. It is because fuel is located high on the tractor. Everything else is below. Failure means fuel has a path to your crankcase. Gravity is constant. You do not pump fuel up to the carburetor. We cannot say our kit will prevent a future leak down. What we can say is this is the best kit available for this application. Future use, operation, and timely maintenance are critical for long term performance of this and the other products we sell.