Machined from billet to OEM dimensions to fit 701 based engines that do not utilize the OEM oil pump. No need for a gasket. They are equipped with a re-usable silicon o-ring for sealing and a new starter bushing. These fit 61x 62t cases, clears all OEM flywheel bolts when correctly installed (No Washer). If you are running any other bolts OR washers it is recommended that you check the clearance between the bolt head and the cover!!