Product Description Specifications Designed specifically for GM GEN III LS1,2 and 6, this rocker stud features an 8mm base thread and a 3/8" rocker thread with a 1.500" effective stud length. Comes with our 16755-KIT and 16765-Kit kits. Category: Engine Components>Rocker Arms Core: N LTL: N MPN: 4554-1 Proposition 65: Y Special Order: Y