They need to be crack tested, shot peened, and then cryo treated. Makes no sense to cryo treat parts without inspecting them and doing a proper surface treatment. Don Potter used to do that to new 280Z stub axles and companion flanges years ago. For $750 you got those parts plus ARP studs, companion flange nuts, bolts, and washers, 280ZX axle nuts, Japanese bearings and seals, and a tube of Wurth SIG 3000 grease.