The Thrust Washer is for Mercury Turbo. It is a flat washer located between a rotating surface and a stationary component. It helps to keep the propeller centered on the shaft when the soft inner prop hub fails to do so under adverse high-torque conditions. The thrust washer is position on the shaft in front of the boat propeller. It supports the axial load or side-to-side motion and prevents movement along that shaft. It provides a surface on which a bearing is being supports. A matching taper on the prop shaft and the washer is one effective design that stops a thrust washer from moving too far forward. Key Features: For Mercury/ Mariner V6/V8 outboards and Mercruiser sterndrives Thrust washer (forward-turbo brand props only) Mercruiser Alpha 1, Bravo 1 Michigan Wheel PM-219 and 031025 style propeller Product replaces: VT1, VT-1, 9-004 Specifications: SKU: VT-1 Brand: HMS Hubs UPC: VT-1 Weight: 0.55 LBS Mercury/ Mariner V6/V8 outboards & Mercruiser sterndrives Thrust washer (forward-turbo brand props only)Mercruiser Alpha 1, Bravo 1 (Michigan Wheel PM-219 & 031025 style propeller) Thrust washer (forward-turbo brand props only)