For 3/8" and 5/16" applications; will also service 1999 through current GM pickups, and 2000 through current Suburban, Tahoe, and Yukon gasoline vehicles. Special low-profile design works in close quarters on GM, Ford, and Chrysler vehicles where there is limited clearance between the fuel line fittings and fuel fitters, fuel rails, or sending units. This tool is designed to access the center port on GM fuel tank sending unit.