Feature: Helps align the front and rear engine covers for proper seal function and longevity. It is critical that the seals be aligned perfectly concentric to the front diameter of the balancer hub sealing surface. Cover Alignment Tool mimics the balancer to center the cover on the front seal OR locates on the ID of the seal bore in the cover without the seal installed. While the Oil Pan Alignment Tool mimics the oil pan thus providing critical alignment of the oil pan and front cover. Billet aluminum & Quality steel. Very tight tolerances for a perfect alignment. This kit is a must have for engine builders and mechanics. Easy to Use: .