This is the newest commercial version for Rancilio now available, although it is also found in the Silvia Pro and Pro X. It includes the o-ring, finger guard and nut, as well as (not pictured - it's inside the nut) the PTFE seal for the ball of the wand.
It is longer than previous wands with an overall length of 200 mm.
Part is present in models:
SILVIA PRO X
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.