Grease trays are important to have on your gas grill. The Napoleon Grease Trays are a convenient way to keep your grill and outdoor living area clean. The Napoleon grills are equipped with highly efficient sear plates that vaporize grease on contact, but sometimes some gets through. That's when the grease lands in the full-length drip pan and is directed to the disposable grease tray. You should check your grease trays every ten grilling sessions to make sure that they're not filled, and put in a new one if they are. Grease trays are an integral part of your grilling maintenance practice and will help keep your Napoleon running for years to come.