Features:1. Made of high-quality aluminum alloy with good toughness and corrosion resistances.2. Easy installation, Comes with a wrench for easy use.3. Suitable for all kinds of DIY handmade model accessories.Product Specification:Size: Outer Diameter: about 26mm/1inchInner diameter: 6mm/0.24inchHeight: 9mm/0.35inchWeight: 15gPacking List:Shaft Coupler*2Screw*4Allen key*1