This Aluminum spacer can be widely used in high-temperature, high-pressure, and highly corrosive pressure, valves, sealing parts of cylinder heads, and industries such as car, steel mills, chemical equipment, and engineering machinery.Specification Material: AluminumColor: SilverSize:6.2mm ID x 10mm OD x 20mm L / 0.24 x 0.39 x 0.79 inch (ID*OD*L)AdvantageMade of durable Aluminum material, which is hard, good performance, good electrical conductivity, corrosion resistance and can be used for a long time.Instruction Easy to use, just need to install on the screw bolts with proper diameter.NOTE: Please select the appropriate size according to your needs.