Champion RC12YC Spark Plug. Bosch - FR8DC, NGK - BCPR5ES, Nippondenso - Q16PR-U11, Autolite - 5224, AC Delco - FR2LSK. This is a Resistor Plug. Fits on most Vanguard and Kohler brands.
Champion RJ19LM Spark Plug. Fits on most Briggs and Tecumseh brand engines. This is a Resistor plug. Replaces Bosch - W7AC, NGK - BR2LM, Nippondenso - W14LM-U, Autolite - 414 and Champion-J19LM