Bonded Seal also known as Bonded Washer,  Dowty seal or Multiseal is a static seal ring. 

The metal ring makes it resistant to high pressures and is used in mechanical, pneumatic and hydraulic applications. 

They are used to seal flange connections; screw couplings; nuts; bolt heads.

The bonded seal consists of a steel outer ring with a fixed vulcanised trapezoidal seal on the inside diameter.

Self-centering bonded seals are also possible! The self-centering version has an additional centering edge that centers the seal and holds it in place to prevent leakage. This Bonded seal can be mounted very easily.

METALS RING: is made of galvanized steel, aluminum or stainless steel.

RUBBER part: comes standard in NBR.

In case of use with chemicals or high temperatures, Viton, silicones or possibly EPDM is a good alternative. the Bonded seal is available in inch, BSP, metric.st enter here...