The company is offering mechanical seal type 521d that is high on quality. Our mechanical seal type 521d is comprehensively used in glass-lined vessels as it acts as double seal. The mechanical seal type 521d that we offer is reliable and can be used without rotating the direction of the seals. attractive features double sealcartridge unitptfe packing as a secondary seal independent of direction of rotation operating parameters speed : up to 2 mssize range : 40 to 150mmtemperature : -30o c to +180 ocpressure : full vacuum to 16 kgcm2.