... / 16mm / 19mm / 20mm / 25mm / 28mm4.specification: F3/8* F3/8, F3/8* F1/2, F1/2* F1/2, F1/2* F3 ... /4, F3/8* F7/8, F3/4* F3/45. nuts: brass / stainless steel ... Type or Annular Type), Outer layer is stainless stainless wire.2) Used in transporting mediums such as air, smoke ... SUS316L.7) Flange material: SUS304, 316 or carbon steel .8) Length: 100 - 4,000mm or custom requirements.Detail ...