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.