Works on 5/16" and 3/8" fuel lines found in 2010 and newer Ford vehicles with 1.6L, 2.0L & 3.5 GTDI, and 6.2L Boss engines. May work on other 5/16" and 3/8" applications. Double ended tool is designed to fit the limited clearance between the fuel line and high pressure fuel pump. Made from durable, flexible acetal.