D42HS and D942HS worm gear transmission double eccentric bidirectional metal hard seal butterfly valves
D343 Triple Eccentric Multilevel Metal Hard Seal/PTFE Seal Worm Gear Transmission Flange Butterfly Valve
D343 Triple Eccentric Multi level Metal Hard Seal/PTFE Seal Worm Gear Transmission Flange Butterfly Valve
D373 three eccentric multi-level metal hard seal/PTFE sealing worm gear transmission flange butterfly valve