Made for APC Folding Prop Blades, Heavy duty Spinner/Hub assemblies. All aluminum. The propeller blades (ordered seperately) attach to an aluminum yoke, no fasteners required. Comes with 3.2mm (1/8") and 4mm collets. Additional collet inserts for other shaft sizes available below in this category. Style of unit is like bottom spinner in sample photo. SKU Number: MPIPA30