RC Boat Propulsion System Kit 4mm Shaft 150mm Length with 3.17mm Motor Shaft Coupler, 55mm 4-Blade Propeller, Stainless Steel Drive Shaft Assembly for DIY RC Boats (3.175mm Motor Shaft - 150mm length)

["This rc boat drive shaft system Includes 4mm stainless steel shaft (150mm), 3.17mm motor coupler, 55mm 4-blade propeller, and full hardware set.","Made of high-quality 304 stainless steel shaft with dual 4x7 flange bearings pre-installed for smooth rotation, corrosion resistance, and long service life.","Equipped with a 55mm 4-blade propeller (M4 thread, right-hand rotation) for stronger thrust and better stability, ideal for RC boats requiring higher torque.","Precision Fit for 3.17mm Motor Shaft: Comes with metal coupler compatible with 3.17mm motor shafts, ensuring secure and efficient power transmission.","Pre-assembled bearings and included tools (set screws, wrench, connectors) make installation quick and simple, perfect for hobbyists and beginners."]