Reproduction of the Original (second style) KG4H, KG7H and Mark 20H Mercury racing engines.  This was used on both versions of the Mark 20H until the deep skeg gear case was released. Do not use this shaft on the deep skeg gear case as a different drive shaft ball bearing is used in that case. Shaft is 18 9/16 inches long uses the 30-20910 (S7K) ball bearing and the thick drive shaft pilot bushing. This is a very good reproduction but not made by Aeroliner Race Boats, LLC.