Flamesources dot com conversion kit. Factory instructions are included. This kit is intended to convert this grille for a North American grille with a tank mounted underneath the grille. These brass orifices are a replacement for grilles that use male threaded orifices. Many bar-b-ques use these types of orifices, and they might retrofit a number of other brands. These are made for that specific Weber model with front control knobs (not side knobs).