10x PP45-023 NBR Self Centering Bonded Washer Self-Centering Type Bonded Washers were originally designed to replace copper type washers in high-pressure systems. These bonded washers comprise of a metal washer and an elastomeric ring bonded inside the diameter. The metal washer prevents over-compression and limits deformation of the elastomeric ring. Advantages; Reliable low and high pressure sealing. High and low temperature capabilities. Bolt torque is reduced with no loss of tightening load. BSP Standard. GBP 1.80 1