Folding propeller lull pusher ................................. For small to medium sailing boats made of ABS plastic. The blades unfold when the engine is switched on. When stationary, they fold from the driving pressure ...................... The blades are stored by stainless steel shafts. Diameter: 40 mm. Can also be shortened as required. Motor size up to 480. With threaded insert brass M3 or M4 ......................... Delivery does not include the ship wave shown. The matching M3 and M4 ship shafts are available in our shop in all sizes in brass and aluminium with ball bearings