Marshall Excelsior Last Chance Adapter. The ME480P Last Chance Adapter allows you to connect a small disposable cylinder to your grill or other gas appliance when your larger tank unexpectedly runs out of propane. A wonderful convenience to ensure that you will have additional cooking time to finish your meal. Depending on the size of your grill, you will be able to extend your cooking time by approximately an hour or more. Note: the disposable cylinder must always be within 45 degrees of the upright (vertical) position when connected to the grill connection. Keep disposable cylinder and grill connection away from open flames, or hot surfaces. Failure to do so can result in explosion, fire hazard or personal injury. QCC x F POL x 1 Inch 20F Full Flow.