The 5" Hose Extension replaces the installed Grease Buster® coupler to make it easier to reach clogged fittings in tight spaces. The Hose Extension is compatible with both Shop Size and  Regular Size Grease Buster tools. It gives flexibility to reach recessed or inaccessible fittings. The hose is 4 inches long and includes a heavy duty 4-jaw coupler to attach securely to your Zerks.   Important Compatibility Notice: The GB19 Hose Extension is compatible only with Grease Buster® units manufactured before May 1, 2026. If your Grease Buster® has a silver coupler, the GB19 will fit. If you have the new black coupler assembly, the GB19 is not compatible.