Convenient and hassle-free: Simple installation makes it the ideal choice for professionals and DIY enthusiasts alike Type: Flange Shaft Coupling, suitable for model shaft connection, great accessories for RC Model motor, etc Suitable for model shafts: Flange coupling for motor shafts with 3mm/4mm/5mm/6mm/7mm/8mm/10mm inner diameter Function: A special coupler, which can fix one shaft to a plane and install other parts on the shaft easily Function: A special coupler, which can fix one shaft to a plane and install other parts on the shaft easily. Double connection points fasten the coupler tightly.