7/16-14 OverSized BIG-SERT Kit cast iron Big or Small Block thread repair p/n 5761E. Kit Includes: drill, counterbore, tap, tap guide, driver, 5 inserts p/n 57611 .600 length & sealer p/n 6020. Also used in rocker stud repair. Used in cast iron blocks where the material thickness is approx. 5/8 or .625 inches. Used after coil style insert failure.