Product Description Specifications Constructed from 6061-T6 aluminum this solid bar stud girdle set for 3/8" stud Ford 289-302 and 351 Windsor ties rocker studs together to properly locate them. Kit includes hex adjusting nuts, set screws and hardware. Category: Engine Components>Stud Girdles Core: N LTL: N MPN: 4013 Proposition 65: Y Special Order: Y