Bobs Machine Trolling Motor Prop Nut Bobs Machine Trolling Motor Prop Nuts are balanced, durable, and reduce noise and vibrations from trolling motors. This model is designed to fit Minnkota trolling motors 80lbs. and up. These prop nuts feature a powder coat finish that is bright and durable. Exclusive to Bobs Machine brand prop nuts, these prop nuts feature a center hole to access the shaft in the event of shear-pin failure. Additionally, this prop nut requires no tools to remove the trolling