Specification Brand : Yeebyee BulletPoint1 : Shaft Couplers Material: made of high quality Aluminum alloy, Surface oxidation treatment,high hardness and excellent performance BulletPoint2 : Shaft Usage: Bore Diameter: 5mm to 8mm / 0.19inch to 0.31inch; Length: 25mm/0.98inch; Outer diameter: 20mm/0.79inch; Type: Plum shaped BulletPoint3 : Flexibility of coupling shaft removes stress between the motor and driving components, The Shaft Coupling can be disassembled and used in combination by itself BulletPoint4 : Super torque can absorb vibration, appropriate a large torque transmission.High hardness,Durable,and excellent response,not easy to loosen BulletPoint5 : The shaft couplers widely used for 3D Printer, CNC machines, DIY Encoder, Servo Motors, Spindle, Step motor, Ballscrew etc. CustomerPackageType : Standard Packaging ExteriorFinish : Silver FinishType : Polished ItemName : Yeebyee 5mm to 8mm Bore Aluminium Plum Flexible Shaft Coupling Servo Stepper MotorJaw D20xL25 Connector Flexible Shaft Couplers for 3D Printer/CNC Machine/DIY Encoder, 2pcs/Pack (5mmx8mm) ItemPackageDimensions_Height : 6.604 centimeters ItemPackageDimensions_Length : 2.2098 centimeters ItemPackageDimensions_Width : 4.4958 centimeters ItemPackageQuantity : 1 ItemTypeKeyword : spider-couplings Manufacturer : Yeebyee Material : Aluminum MetalType : Aluminum ModelNumber : YE010-1 NumberOfItems : 2 PartNumber : YE010-1 ProductDescription : Product Name: 5mm to 8mm Bore Aluminium Plum Flexible Shaft Coupling Servo Stepper Motor Jaw D20xL25 Connector Flexible Shaft Couplers Material: made of high quality Aluminum alloy, Surface oxidation treatment,high hardness and excellent performance Type: Plum Shaped Shaft Usage: Bore Diameter: 5mm to 8mm / 0.19inch to 0.31inch Size( L*D): L25mm x D20mm/0.98inch x 0.79inch Main Color: Silver Tone,Red The shaft couplers widely used for 3D Printer, CNC machines, DIY Encoder, Servo Motors, Spindle, Step motor, Ballscrew etc. Package Included: 2pcs Plum Shaft Couplers 1pcs Allen Key Please Note: The shaft coupler is not elastic, can not modify the concentricity. Shaft must be located in a straight line. If your equipment is eccentric already, then it will make noise and cause off-centering. Any question or problem, do not hesitate to contact us, we will reply you within 24 hours As Manual measurement, please allow slight errors on size The color may exist slight difference due to different screen displays