Art. 1970s300 Valvola di ritegno a disco, corpo in bronzo 85.5.5 (Rg 5), tenuta metallica, serie PN 40
Art 1971s300 Valvola di ritegno a disco, corpo in bronzo 85.5.5, tenuta PTFE, serie PN 40
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Art. 1970s300 Lift check valve piston type, with body in bronze 85.5.5.5 (Rg 5), brass OT 58 disc, metal to metal seat, series PN 40
Art. 1971s300 Lift check valve piston type with body in bronze, seat of the disc in PTFE, metal seat of the body, series PN 400