SEI MARINE PRODUCTS- Yamaha Gearcase Seal Kit 66K-W0001-20-00 200 225 250 HP 2 Stroke 4 Stroke This gearcase seal kit replaces OE#: 66K-W0001-20-00 and fits Yamaha outboard lower units with the following applications: 2 Stroke 1990 to current (200-250Hp) 3.1 & 3.2 L engines, and4 Stroke 2004 to current (200-250Hp) 6 Cylinder engines.