This connector plate outside is made of aluminum alloy, which is strong and durable. Widely used in construction industry aluminum frame structure, such as 3D printer, CNC router, CNC laser cutting machine, robot project and so on. The 5 hole placement is for vertical connections designed and very practical.Infinite positioning possibilities for maximum flexibility in your own design.Uses advanced technology through excellent craftsmanship to achieve a smooth surface that will not hurt your hands when working.Specification:Item Type:Connection PlateMaterial:Aluminum AlloyNumber of Holes: 5.Color:SilverModel Thickness(Approx.) Hole Diameter(Approx.) Hole Spacing(Approx.) Length(Approx.):2020L: Shape 4mm/0.2inch 5mm/0.2inch 20mm/0.8inch 60mm/ 2.4 inchPackage list:4 x connect plate outside