Detailed Product Description specification:DN20-100,1' -4',standard:DIN ISOmaterial quality:sus304,SUS316Lapplication:beer,dairy,beverage,pharmacy Type:welded,quiack-installed,threadedWorking principle:remote-controlled operation by the driving gear of manual operation by the handle.Three driving forms:normally closed,normally opened and normally opened&closed by two air flues separately.packing: ...