The Hastings Piston Ring Set 2M5523 is a premium set of piston rings made of Plasma Moly material. It includes three thicknesses - 1/16, 1/16, and 3/16 inches. Designed for a 4-inch cylinder bore diameter, this drop-in set is manufactured in the United States by Hastings. The item weight is 1 pound, and it comes with interchange part number Speed Pro R8902. Ideal for car and truck engines, this piston ring set offers high-quality performance for your vehicle.