Includes (2) Main burner control knobs (gray) These fit the manifold that was redesigned with new valves in 2012. Measures 2-3/8" in diameter Fits 1/4" diameter shaft Genuine Weber OEM Part Includes (2) Main burner control knobs (gray) These fit the manifold that was redesigned with new valves in 2012. Fits the following Weber Summit models: 97121001 (2012) (LP) Summit E-420 Grill - Black 97221001 (2012) (NG) Summit E-420 Grill - Black 97120001 (2012) (LP) Summit S-420 Grill - SS 97220001 (2012) (NG) Summit S-420 Grill - SS 1740001 (2007) Summit S-450 Gas Grill 97320001 (2012) (LP) Summit S-620 Grill - SS 7320001 (2010-2011) (LP) Summit S-620 Grill - SS 7321001 (2010-2011) (LP) Summit E-620 Grill - Black 97321001 (2012) (LP) Summit E-620 Grill - Black 97420001 (2012) (NG) Summit S-620 Grill - SS 97421001 (2012) (NG) Summit E-620 Grill - Black