Rancilio Silvia Steam Wand / Valve Shaft O-Ring This 6.07mm ID x 1.78mm EPDM 105 o-ring is Rancilio's stock replacement (Rancilio #36402001) for the Silvia's steam wand and valve shaft, not the o-ring at the wand tip, which is a different part. It's also used elsewhere on Rancilio equipment as a solenoid flange o-ring and on the Epoca's single-group group head flange. SPECIFICATIONS 6.07mm ID x 1.78mm thick; EPDM 105 rubber COMPATIBILITY Fits: Rancilio Silvia steam wand/valve shaft, pre-2008 (Versions 1-2) typically need 2 each for wand and valve, 4 total; post-2008 (Versions 3-5) need only 2, for the valve only, not the wand Works with: Rancilio solenoid flanges and the Epoca group head flange INSTALLATION DIY-friendly for an experienced home user; a technician job if it's your first time into the valve. PRO TIPS Know your Silvia's version before ordering quantity, pre-2008 machines need o-rings in both the wand and the valve (4 total), while 2008-and-later machines only use this o-ring in the valve, so you'd need just 2. Always lubricate before reassembly, a dry o-ring is far more likely to twist, pinch, or tear during installation.