The DTR bell is the most important part of a DTR. Its design has been perfected and tested over years. The bell starts its life from a piece of nylon 6/6 rod stock. It is then machined on a lathe to become a extremely durable and versatile part of a DTR. There are 4 threaded holes on the top of the bell. These are for different screws that allow the DTR to be used multiple ways.