The Derringer RDA Clone by Tobeco is a short and simple 3 post RDA. This RDA is one of the shortest available to give you the most compact vape set up! It has 3 interchangeable airflow holes on each side for either dual or single coil. Due to the compact size and deep well, it provides an especially flavorful and warm vape! The silver-plated brass contact pin is NON-adjustable and is one shaft with the center post.