SCAT 10mm 4140 chromoly head stud kit for type 1 engine (16 studs) prevents head stud stretch and breakage, and these quality units from SCAT will NOT break or stretch! Kit comes with (16) studs, (16) washers, and (16) nuts. 145,000PSI Tensile Strength, designed for stock and High Performance Engines. If you have less than 250hp NA, or 400hp Turbo, you do not need anything ''better'' than these!