So let's look at the structure of a bomb kilometer. Now, bomb calorimeters are composed of two cylinders, a large one and a small one. The outer one is called the insulated chamber and it insulates the entire system. So energy is not allowed to leave our bomb kilometer. The intermodal chamber is called a steel bomb and it's basically the location of our reaction. This is where our reaction occurs and it's made from steel so that the gas can't expand our system.