1.These joining plates are made of stainless steel of good quality hard and durable can prevent rust and erosion thus last for a long time.2.Perfect for household if the chair table desk bed are shaking or broken these flat straight brackets are very important fastener to make furniture stay firm.3.Package come with the screws for easy installation. But it would be hard for us to know the length of the screw your particular project would require you can substitute other suitable screws by yourself if you think you need it. Specification:Material: Stainless SteelFinish: Barrel PolishingPlate Size: 50 x 16 x 2mm / 1.97" x 0.63" x 0.1" (L*W*T)Screw Size: 4mm x 19mm / 0.16" x 0.75" (Thread.Dia *L)Mount Hole Diameter: 4.5mm / 0.