Please Noted:
The rigid coupling is a 90 degree fastening design and is fastened by four machine meter screws
Material: No 45 Steel

Package include: Coupling x 1+ machine screw x 4 + wrench x 1 (Only one wrench is delivered per order.)

Size description:
1. The following 6 types, the outer diameter is 14mm, length is 22mm, screw hole diameter is 4mm:
3.17mm-3.17mm, 4mm-4mm, 4mm-5mm, 4mm-6mm, 5mm-5mm, 5mm-6mm, 5mm-8mm, 6mm-6mm, 6mm-8mm, 8mm-8mm

2 .The following 3 types, the outer diameter is 16mm, length is 22mm, screw hole diameter is 4mm:
6mm-10mm, 8mm-10mm, 10mm-10mm

3. The following 3 types, the outer diameter is 20mm, length is 22mm, screw hole diameter is 5mm:
8mm-12mm, 10mm-12mm, 12mm-12mm