Get current pricing for Oem, OEM-19459-ID Is A Perkin Elmer 3 3/8 (dn50) Conflat Bellows Vacuum Valve That Steps Down To 2 3/4. 3 3/8 Or Dn50 Conflat On Top 2 3/4 On Bottom Fla . Product Category: Lab Equipment, Sub Category: Process Vacuum: