This listing is for a set of piston rings from Hastings Manufacturing that are made in the USA. Set includes all the rings needed for 8 pistons. Top Ring Width: 1.5mm, and 2nd Ring Width: 1.5mm Oil Ring Width: 3.0mm. This set of rings are compatible replacements for the following Chevy GM engines that have ring groove widths of 1.5mm Top Ring & 1.5mm Second Ring & 3.0mm Oil Ring. (Please measure Your ring grooves before ordering!) 350 CID (5.7L) 1996-2000 Vortec VIN: R, 364 CID (6.0L) 1999-2004 Vortec VIN: H, N, U - LS2. VIN refers to the 8th character in your vehicles ID in lower dash. These are Available in STD .020" .030" .040" & .060" Bore over Sizes.