ARP BB Ford MSK (ARP Part #155-5402) is a precision-engineered fastener from ARP, the world leader in high-performance fasteners for the automotive industry. These fasteners are manufactured to the highest standards for use in professional engine builds and motorsport applications. Every ARP fastener is precision CNC-machined from premium raw materials. The manufacturing process includes: Cold-forging for superior grain structure Precision thread rolling (not cutting) for maximum strength Heat treatment to exact specifications Magnetic particle inspection for quality assurance Applications: Ideal for high-performance street engines, racing applications, turbocharged and supercharged builds, and any application where fastener reliability is critical. Trust ARP - the choice of professional engine builders and motorsport teams worldwide. When engine reliability matters, choose ARP.