Buffer, Valve, Safety, Pfeiffer, DUO, Part# 390024 – vacstellar

This is a buffer component for the safety valve on Pfeiffer DUO and UNO series vacuum pumps. It cushions the valve movement, reducing noise and preventing metal-to-metal contact during operation .

This buffer is used in many Pfeiffer DUO and UNO pumps. It fits models like the DUO 1.6, DUO 2.5, DUO 3, DUO 5, DUO 6, DUO 11, DUO 20, and UNO 6 . It is also used in larger pumps like the DUO 120A and DUO 250A .

Over time, this buffer can wear out or become hard. If it fails, the safety valve may rattle or not seal correctly. Replacing it is a simple fix that helps keep the pump running quietly and safely.

If you are already servicing your pump, replacing this buffer is a smart move. It is a small part that makes a big difference in how smoothly your pump operates.