Features and Benefits: Unique and patented design works on 2004 newer Ford F-150 pickup trucks with 5.4L 3-valve Triton V-8 engines Extension is part of the socket and easily fits down spark plug tube into the cylinder head Soft rubber insert holds and protects spark plug during removal and installation Socket has 3/8 inch drive for use with a ratchet or breaker bar Socket end is 9/16 inch his unique and patented design works on 2004‐newer Ford F-150 pickup trucks with 5.4L 3-valve Triton V-8 engines. The socket end is 9/16 inch and the soft rubber insert holds and protects spark plug during removal and installation. The extension is part of the socket and easily fits down spark plug tube into the cylinder head. The socket has 3/8 inch drive for use with a ratchet or breaker bar.