This is the large ignition box for 3 burner barbecues, including Legend 3000, 3500, Patio Mate 3, Heritage 300 and Legend 3EU. It is also used on the 3 burner side of Legend5000/5500. Each 3 burner barbecue has two ignition boxes. They are called Ignition Box 3B Large and Ignition Box 3B Small. They can be identified simply by comparing the sizes of the two boxes in your barbecue.