This is the complete high thrust conversion kit for Yamaha F15 / F20 outboard motor - propeller, thrust ring and special prop nut and washer. These were all purchased brand new and kept as a spare, I don’t think the propeller was ever actually fitted, however it does have marks etc from being stored in a locker onboard the boat. This kit converts a standard Yamaha 15 / 20hp four stroke engine into a high thrust version which is better for heavier displacement hulls / yachts / fishing boats etc, and gives increased thrust in reverse compared to the standard propellers.
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