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: 4.2mm ID x 10mm OD x 12mm LCompatible Screw Size: 5/32" , M4 Screws BoltsPackage List: 10 PCS M4 Aluminum spacerAdvantageMade 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.