O-RING 02037. Replaces part (same size as) EPDM rubber version M_71. There are more than one application for this o-ring (originally used and designated for the Mairali, thus the 'M' part number), for example, the Rancilio Z11 RE manual group and steam valves, Futurmat water expansion valve o-ring as well as the super old Carimali steam and water valve shaft o-ring.
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.