The Thomas Jefferson High School for Science and Technology InvenTeam invented the Automatic Precise Tourniquet (APT) to facilitate a faster and more convenient emergency response in areas lacking adequate medical services, and to simplify the application of an automated emergency tourniquet for untrained medical professionals. The APT inflates to capacity within 45 seconds to sufficiently stop arterial blood flow, and weighs less than five pounds. The APT consists of: • a pressure-detecting cuff that is applied to the limb in need of medical aid, • a pressure regulator that uses 16 gram compressed CO2 cartridges to inflate the cuff, and • an Arduino that controls the cuff and regulator. The device is powered by a 9V battery and has an LCD interface that visually instructs the user on operation. The APT is designed to be carried with ease and is small enough to be stored in bags such as backpacks and travel cases.