This listing is for a brand new set of moly piston rings from Hastings Manufacturing that are made in the USA. Set includes the rings for 8 pistons. Part Number: 2M683 30 Bore Size: 4.280" Top Ring Width: 5/64" 2nd Ring Width: 5/64" Oil Ring Width: 3/16" This set of rings are a compatible replacement for the following engines that have 4.280" bore size and ring groove widths of 5/64" x 5/64" x 3/16". 427 CID (7.0L) 1966-1969 & 454 CID (7.4L) 1970-1990