O-RING 6,07 X 1,78 EPDM 105, 36402001. Stock O.E.M. replacement part Rancilio Silvia Steam Wand/Valve Shaft O-ring. In the pre-2008 (Versions 1 and 2) Silvia, you will more than likely need two each of these for both the steam wand and/or valve. In the post-2008 (Version 3, 4 and 5) only two are needed for the steam valve, and they are not used in the wand.
Also used by Rancilio as a solenoid flange o-ring, as well as the Epoca (one group) group head flange.
As with any o-ring and moving parts, lubrication is highly recommended.
WARNING: This product can expose you to chemicals including lead, which are known to the State of California to cause cancer, birth defects, or other reproductive harm. For more information, go to www.p65warnings.ca.gov.