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 filters, fuel rails, or sending units. Both tools are designed to access the center port on the GM fuel tank sending unit. No. 6509 � For 3/8" & 5/16" applications. Will also service 1999�current GM pickups, and 2000�current Suburban, Tahoe, and Yukon gasoline vehicles.