Features 

• The length of the coupling: 22mm
• Outer diameter according to the different aperture there are two: 14mm, 16mm

The following six kinds, the coupling diameter of 14mm, length of 22mm: 

4-4 for one side of the hole diameter 4mm, the other end of the hole diameter of 4mm; (side hole using M4 machine screws) 
5-5 shows one side of the aperture 5mm, the other end of the hole diameter of 5mm; (side hole using M4 machine screws) 
5-8 for one side of the hole diameter of 5mm, the other end of the hole diameter of 8mm; (side hole using M4 machine screws) 
6-6 side of the hole diameter 6mm, the other end of the hole diameter of 6mm; (side hole using M4 machine screws) 
6-8 for one side of the hole diameter 6mm, the other end of the hole diameter of 8mm; (side hole using M4 machine screws) 
8-8 for one side of the hole diameter 8mm, the other end of the hole diameter of 8mm; (side hole using M4 machine screws) 

The following three kinds, the coupling diameter of 16mm, length of 22mm: 

6-10 for one side of the aperture 6mm, the other end of the hole diameter of 10mm; (side hole using M4 machine screws) 8-10 for one side of the aperture 8mm, the other end of the hole diameter of 10mm; (side hole using M4 machine screws) 10-10 for one side of the hole diameter of 10mm, the other end of the hole diameter of 10mm; (side hole using M5 machine screws)