Specification:Name: Brass Rigid Motor Shaft Coupling CouplerMaterial: BrassOuter Ddiameter: 9mmLength: 20mmInner Diameter: 2mm 2.3mm 3mm 3.17mm 4mm 5mm 6mmFeatures:High hardness, nice quality, lengthy life, strong locking, strong and durable.Note:1.Each coupling will be despatched with four screws.2.Only one wrench will be sent with each order.Package :Packing : Plastic bag / Carton box.Quantity : According on your Choose!