Compatible with all 1958-2000 Chevy Big Blocks 348 366 402 409 427 396 454 502 running headers with up to a ½” Flange Thickness
These are High Grade 18-8 Stainless-Steel Steel 3/8-16x1” Bolts and Washers That will NOT rust or Corrode like the chrome or steel ones sold. These Use a 5/16” Allen Wrench/Socket
Meets or Exceeds Industry Standard ASME / ANSI Specifications