Actually, this oven is composed of two parts. One part is the removable inner pot where you can put food in and place it inside the oven. As for the barbecue modes, there are two: one is the normal mode and the other is the high-temperature mode. In the normal mode, the shell is separated into two half circles, one on each side. Then, you can pull out a thin semi-circular part from the bottom to cover the inner pot.