100% brand new and high quality. Specification: Material: 45# steel,hardened by heat treatment, and then electroplated 3mm/4mm/5mm/6mm Inner Diameter: 3mm/4mm/5mm/6mm Cylindrical Diameter: 10mm Overall Height: 12mm Bottom Diameter: 22mm Fixed Hole Screw: M3 Fixed Hole Distance:16mm 7mm/8mm Inner Diameter: 7mm/8mm Cylindrical Diameter: 16mm Overall Height: 13mm Bottom Diameter: 32mm Fixed Hole Screw: M4 Fixed Hole Distance: 26mm 10mm/11mm/12mm Inner Diameter: 10mm/11mm/12mm Cylindrical Diameter: 18mm Overall Height: 13mm Bottom Diameter: 32mm Fixed Hole Screw: M4 Fixed Hole Distance: 26mm Note: 1.Please allow 1-2cm error due to manual measurement. pls make sure you do not mind before you bid. 2.Due to the difference between different monitors, the picture may not reflect the actual color of the item. Thank you! Package includes: 1 x Coupler