Multi spring balance & unbalance back to back mechanical seal ME280D / ME285D series are developed for universal application. Their compact design makes them suitable for use in all types of Centrifugal Pumps. Torque transmission from retainer shell to seal ring is done through drive lugs. All components are held together by a Snap Ring which makes installation and removal easily. As all parts are interchangeable, so secondary seal ‘O’ Ring can be converted into the ‘PTFE’ by changing only the Seal Ring and the Elastomer. The concept is ideal for stock realization. This seals are factory assembled and dynamically tested.