This listing is for (8) +.030 over size hyper Pistons and matchingMoly Ring Set compatible replacements for Chevrolet 350 Vortec 5.7 1996-2002. VIN code "K or "R". VIN refers to the 8th character in the vehicles ID in lower dash reading from left to right. This kit is for a 4.030" Bore Engine. Dish pistons with 4 valve relief. These pistons have 1.50mm-1.50mm-3.0mm ring grooves & can be free floated. LR63 locks not included & must be purchased separately.