YamahaGrizzly 660 2002-2008
Yamaha Raptor 660 2001-2005
Yamaha Rhino 660 2004-2007

Nuts are machined from billet high tensile steel and heat treated
Studs are heat treated 180,000 PSI aircraft alloy steel
Both nut and stud have rolled threads for the strongest possible threads
Both nut and stud are black oxide treated for enhanced corrosion resistance

KPMI Cylinder Head Studs are made from 180,000 psi yield strength, fine grain,heat treated, aircraft grade alloy steel. When you want a stud that meetsproof-stress and maximizes clamping force, look no further. KPMI rolls thethreads, heat treats and then centerless grinds the entire body of the stud.Rolling the threads creates the toughest and strongest thread possible andcenterless grinding removes notch sensitivity. The final process for all KPMIStuds is to encase the entire stud with premium corrosion resistant treatmentof Black Oxide. Congratulations on your choice to purchase a stud that meetsand exceeds your stock-replacement of high-performance needs!

KPMI nuts are single point machined from high tensile strength Aircraft AlloySteel. During the machining process close tolerances and smooth surfacefinishes are maintained. Two critical factors for achieving correct fit andtorque. After machining, the nuts are heat treated to a specific depth. Thiscreates hard, wear resistant working surfaces, while retaining a ductile coreto prevent cracking under load. The premium black oxide treatment providesexcellent corrosion resistance and appearance.