Activator Methods is based on the postulate that understanding body mechanics and force is the key to understanding how to move bones. A leg test is utilized to tell the doctor if the subluxation exists, chiefly in the lumbo-sacral area or cervical region of the spine. With further research into body mechanics, W.C. Lee D.C. and A.W. Fuhr D.C. were able to analyze the body and produce from the analysis consistent changes using a light non-force specific chiropractic adjustment. Lee and Fuhr understood that force was not necessary to correct subluxations in the body. Two components are necessary for fast, effective reduction of nerve pressure caused by subluxations. They are speed and line of drive. Speed and line of drive are what make chiropractic the distinct and dynamic art and science that it is. The activator instrument was designed to deliver this specific dynamic thrust. It is a small hand-held gun-type mechanism that delivers a sharp percussive thrust upon triggering. The activator instrument controls the force and speed of the adjustment exceptionally well and with the activator, the line of drive can be more specific.