Specification BulletPoint1 : The diameter of the bore for ball screw is 17mm in default, the diameter of the bore for motor shaft is as 0.625 inch 15.875mm in default, if your motor size is others, please tell us BulletPoint2 : Material: Aluminum alloy, polyurethane Type: Plum shaped BulletPoint3 : Super torque can absorb vibration, appropriate a large torque transmission. High hardness, Durable, and excellent response, not easy to loosen BulletPoint4 : Flexibility of coupling coupler shaft removes stress between the motor and driving components BulletPoint5 : As a factory seller, we can provide the coupling coupler with customization, please contact us ExternallyAssignedProductIdentifier1 : 0743791925014 ExternallyAssignedProductIdentifier2 : 743791925014 ItemName : Mssoomm 2Pcs Aluminium Plum Flexible Shaft Coupler Coupling for Ballscrew 25mm, with Customization Bore Diameter for Motor Shaft of CNC Ball Screw Kit ItemTypeKeyword : spider-couplings Manufacturer : Mssoomm Material : Aluminum MetalType : Aluminum NumberOfItems : 1 PartNumber : MS-SFU2505-L100MM-NUT ProductDescription : Specifications: Brand: Mssoomm Material: Aluminum alloy Model: For Ball screw 25mm This package includes: 1pcs Coupler / Coupling ProductSiteLaunchDate : 2020-05-18T01:31:09.426Z Size : Coupler Style : 25mm Ballscrew UnspscCode : 31161500