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Features:
1) DN25 - DN400
2) When medium passes valve forward, the disc opens under pressure of the medium
3) Disc closes by a spring when the medium passes valve backward
4) Disc closes slowly until fully closed so to eliminate noise and water pressure
5) Suitable for petroleum, chemicals, food, medicine, water supply and drainage,
and energy systems

Inner packing:
Carton

Outer packing:
Wooden cases