Specification:Material: MetalType:3-2.3 mm / 3-3.17 mm / 3-3 mm / 4-2.3 mm / 4-3 mm / 4-3.17 mm / 4-4 mm / 4-6 mm / 5-3 mm / 5-4 mm / 5-5 mm / 5-6 mm / 5-8 mm / 6-8 mm / 8-8 mm /Size:2.3-2.3 mm / 2-2.3 mm / 2-2 mmUniversal Joint Outside Diameter: eight mmUniversal Joint Length: 18 mmSide Screw Fixing Hole: M32.3-3 mm / 3-3 mm / 3-3.17 mm / 3.17-3.17 mm Universal Joint Outside Diameter: 9mmUniversal Joint Length: 23 mmSide Screw Fixing Hole: M33.17-4 mm / 4-3 mm / 4-4 mm / 4-2.3 mmUniversal Joint Outside Diameter: 9mmUniversal Joint Length: 23 mmSide Screw Fixing Hole: M35-4 mm / 3-5 mm / 5-5 mm / 4-6 mm / 5-6 mm / 6-6 mmUniversal Joint Outside Diameter: 11mmUniversal Joint Length: 23 mmSide Screw Fixing Hole: M45-8 mm / 6-8 mm / 8-8 mmUniversal Joint Outside Diameter: 14mmUniversal Joint Length: 35 mmSide Screw Fixing Hole: M4( This model has a circlip design and is fixed, so it's kind of tight, which is regular )Product scope of application: The metal common joint is suitable for the use of the immediately shaft of the motor, and is suitable for the use of various metals akin to mannequin cars, mannequin boats, and robots!Note:Please allow 1-3mm error due to manual measurement. pls ensure you do not mind earlier than you bid.Due to the difference between different monitors, the image won't reflect the actual shade of the item. Thank you!Package Includes:1 x Shaft Coupler