standard:Q/TF-B27P.01,BS,ISO,DIN
PN10,PN16
DN50-300
material:grey cast iron,ductile iron
leakage:GB/T 13927 class A

There is one large and one small orifices. The large one is used to intake and release large amount of air and the small one is used to release the air during the course of water supplying. The main pipeline is DN400-1600mm.