SEI Yamaha V6 2 Stroke 1.81:1 30" Shaft Replacement Lower UnitNote for purchasing: You must verify your Gear Ratio. Call for application assistance if needed, and have your engine serial number ready when calling. Not Designed for Yamaha F250 fourstroke 250 HP motors. SE421, 1.81:1, 20" Driveshaft; Standard Right Hand Rotation; 76 V6 2 Stroke 3.1L & 3.2LYamaha Outboards; Includes Sterndrive Engineering's No Fault Warranty for 3 Years; Measuring Guide: Use 20" models when from the top of the driveshaft to the mounting surfaces measures 22.5"; Use 25" models when from the top of the driveshaft to the mounting surfaces measures 27.5"; Item is subject to a 20% restocking fee (Boat Covers, Bimini Tops, Outdrives, Drop Ship Items and Special Order Parts)!**Year, Serial Number, and Horsepower are required to order. Please contact us with this information after you place your order otherwise processing will be delayed.