This is a new old stock set of  Alcon Raybestos 1.65" (42mm) x 12.91" (328mm)  12 bolt, 72 vane racing rotors. Part #PR2026L&R for use w/ PFC pad shape 7773 ect.
These have been mounted, burnished & dismounted. Not raced. Very popular choice for the Raybestos PC1005 and many other big Nascar 6 piston front race calipers.