1.Tough, flexible rubber construction, high temperature resistance, corrosion resistance and strong sealing. 2.Replacing the washers will create a better seal and help prevent leaks for the future. 3.Intended for use in pipe, valve, hose nut and other plumbing repair or retrofit applications. Widely used for lighting, mounting, industrial, workshop, equipment, etc. 4.It Can prevent leaking and provide a positive shut-off, stopping the leak saves both and energy, effectively reducing the vibrations by absorbing the shock to a certain extent. 5.These rubber flat washers can be used in temperature range from -22 degree F to 248 degree F (-30 degree C to 120 degree C), provide long-term use for your plumbing needs. Material: Rubber Thickness: 2.2mm / 0.087-inch Inner Diameter: 10mm / 0.39-inch Outer Diameter: 20mm / 0.79-inch Package Content: 50(+/-2%)pcs x Flat