The Check Nut Wrench is used to tighten, loosen, and properly seat check nuts used in coupling supply line adapters and certain return line assemblies. Its geometry allows firm engagement with the nut surfaces, helping prevent slippage while applying controlled torque. The wrench provides the clearance needed to access fittings in restricted areas, supporting accurate adjustment without disturbing surrounding lines. By ensuring each check nut is properly seated, the wrench helps protect hydraulic lines from loosening, leakage, or misalignment.Attributes:• 2 special hex bits required to remove and install SAE O-ring plugs.• Wrench used to couple supply line adapters and some of the return line assemblies.• Special application wrenches for tight and confined spaces.Applications: The Check Nut Wrench is used to tighten or loosen check nuts on supply line adapters and selected return line assemblies. It helps maintain secure coupling, prevent leaks, and support stable operation of hydraulic line connections during installation or service work.