OEM stands for Original Equipment Manufacturer, which means the parts are made by the same company that make the parts for the manufacturer.
Part #'s
02E-305-051-C / 02E305051 C / 02E 305 051 C / 02E305051C
02E-305-051-B / 02E305051 B / 02E 305 051 B / 02E305051B
02E-398-051 / 02E 398 051 / 02E398051