ARP uses a premium grade 8740 alloy that is rated far superior to "aircraft" quality. Then, each stud is placed vertically in special racks and precisely heat-treated to 200,000 psi. ARP studs are thread rolled after heat-treat, which gives them about 1000% (that's ten times) better fatigue strength than those studs that are threaded prior to heat-treat (a very common industry practice). It costs a lot more to do it this way, because it's tough on tooling, but the results are well worth the extra effort.
 

Brand:ARP
Part Type:Cylinder Head Fasteners
Product Line:ARP Pro Series Cylinder Head Stud Kits

UPC:672036008185
Fastener Style: Stud
Undercut Stud: Yes
Head Style: 12-point
Fastener Material: 8740 chromoly
Fastener Finish: Black oxide
Washers Included: Yes
Cut to Fit: No
Quantity: Sold as a kit.