This listing is for (8) Standard bore 4.00" hyper Pistons and matching Moly Ring Set compatible replacements for Chevrolet 350 Vortec 5.7 1996-2002. This kit is for a 4.00" Standard Bore Engine. Dish Pistons with 4 valve relief. These pistons has 1.50mm-1.50mm-3.0mm ring grooves & can be free floated but LR63 locks not included & must be purchased separately.