In most cases, it just isn't worth it to try to rebuild your old, cracked, worn-out cylinder heads or to bore the stock cylinders again. S&S Cycle 74 In. Shovelhead top end kits provide everything you need to replace the top end. Pistons are pre-fit to the cylinders, so there is no machine work done and very little down time. Compression pistons come complete with rings and wrist pins, manifold clamps seals, all required hardware, and gaskets. You can't go wrong with these kits. When it comes to reliability and durability, you need quality parts. Fit and quality mean life for your Harley®!