This steel 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: Carbon SteelSize:6.5mm ID x 12mm OD x 11mm LCompatible Screw Size: 1/4 inch , M6 Screws BoltsColor: BlackAdvantageMade of durable Carbon Steel 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.