Genuine Weber replacement part. Set of two "lighted" control knobs for main burners. Fits Summit 400/600 Series model years 2007-2011. Diameter is 2-3/8". The back half of the knob has a translucent body for emitting light. Features a red Weber Kettle logo on a chrome top, gray finger grip notches and "Off/Ignition/High To Low" graphics which continue approximately halfway around the knob. Use this control knob if the manifold has never been replaced. If the manifold has been replaced and only knobs are needed, order part #91538. If replacing knobs on a 2012 or later model, use part #91538.