The hard anodizing helps prevent galling and the alum. provides light weight while providing a safety factor in the event of a supercharger backfire saving your supercharger or manifold.
Coarse end is .875", fine thread end is .975" and shoulder is .500". End to end is 2.510". Stud is made from 2024 alum.
These studs are sold individual but if wanting a kit with nuts order #900-0010.