1)Material:SUS304,SUS316L 2)Connection:welded, threaded, clamped 3)CE: ISO9001 Features:1) Material quality: AISI304, AISI304L, AISI306, AISI316L 2) Seal: silicone, EPDM3) Standard: DIN, SMS, 3A, ISO, IDF hygenic and sanitary welded pipeline sight glass