... , DIN, 3A,etc Material:AISI304, AISI316L Technical parametersreversing valve(reverse flow valve,reversal valve)Size: DN25-104and 1”~4”Standard:ISO, DIN, 3A ... , opened and closed by two air flues separatelySeal ring:Silicon rubber, EPDM or FPMApplication:dairy, beverage, food, beer, pharmaceutical, biotechnology, ... your special request. OEM is welcome too. Sanitary pneumatic reversing valve (BLS)