This listing is for (16) brand new rocker arm studs and guide plates kit. Kit includes 8 guide plates and 16 rocker arm studs. The guide plates are the Flat style for 5/16" diameter push rods. The rocker arm studs are the screw in style with 7/16" Top Rocker arm Threads and 7/16" Bottom thread rocker arms. This kit can be used in many small block Chevy 262, 265, 267, 283, 302, 305, 307, 327, 350 and 400 V8 engines. Rocker studs are: 2.560" Overall stud length 0.795" Screw-in thread depth 0.890" Adjuster thread depth 7/16"-20 Fine thread 7/16"-14 Coarse thread.