Specification:Shaft Coupler Flexible Coupling Stepper Motor Connector for CNC Motor D18 L25Shaft size : please prefer when you position order.Length: 25mmDiameter: 18mmMaterial: AluminiumQuantity: 50pcsShaft coupler Often used to connect servo motor, stepper motor, encoder, screw driving, machine platform, etc.*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-We have beneath flexible coupling, please click on to order, thank you!D18 L25(3-8)D20 L25(4-8)D25 L30(5-12.7)Jaw plum spider coupling D20 L25(4-8) D20 L30(4-10)D25 L30(5-12.7)D30 L35(8-16)D30 L40(8-16)D40 L66(8-22)D55 L78(10-30)D65 L90(15-35)*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*We even have beneath coupling: