Specification Brand : cizihuu BulletPoint : Please select the size you need. BulletPoint1 : Size: Outer diameter X length: D12mm x L18mm, Inner Diameter 3.17mm. BulletPoint2 : Made of high-quality brass, with high torque rigidity, low inertia and good sensitivity. BulletPoint3 : Hexagonal rigid coupling, with 4 fastening holes on the surface, equipped with machine screws and matching hexagon wrench. BulletPoint4 : The elongated hexagonal coupling has the function of extending the shaft;The motor using this coupling can effectively extend the transmission distance, Can be used for electric car toys, robots, remote control model motors, etc. BulletPoint5 : This coupling can be used to connect the landscape motor shaft to Nine Rainbow, and it can also be used to connect the motor shaft to other model accessories. Color : brass color ExteriorFinish : Brass ExteriorFinish1 : Silver ExteriorFinish2 : Aluminum ExternallyAssignedProductIdentifier1 : 0359923984929 ExternallyAssignedProductIdentifier2 : 359923984929 ExternallyAssignedProductIdentifier3 : 00044861416174 FinishType : Polished GpsrSafetyAttestation : 1 IncludedComponents : Unit^Instruction Guide ItemName : Rigid Flange Coupling Motor Guide Shaft Coupler Motor Connector,2PCS Inner Diameter 6mm ItemPackageDimensions_Height : 12.2 centimeters ItemPackageDimensions_Length : 1.6 centimeters ItemPackageDimensions_Width : 10.6 centimeters ItemPackageQuantity : 2 ItemTypeKeyword : set-screw-couplings Manufacturer : cizihuu Material : Material,Steel MetalType : Alloy Steel ModelNumber : L099H NumberOfBoxes : 1 NumberOfItems : 1 PartNumber : 4mZ4pkhmB29-9 ProductDescription : Standard or Nonstandard:Standard Flexible or Rigid:Rigid Material: 45# Steel