The Wilwood 5-Bolt Drive Flange with O-Ring create a leak proof seal. There is no need to use gaskets or sealer to retain differential oil. Our drive flanges continue to have long standing reputation for durability. These five bolt drive flanges are machined from 7075-T6 alloy and have a 24 spline count. Each five bolt drive flange kit includes the end plate with screws and Grade-8 drive bolts with hardened washers. These flanges cannot be used on 1 ton axles and hubs due to interference.