The Topeak JoeBlow Booster pump makes it easier to install tubeless tires. This pump has an integrated aluminum air chamber that stores an air charge of one liter, up to 160psi / 11 bar, to quickly fill your tire and ensure the proper bead seating on a tubeless rim. Once you flip the selector from CHARGE to INFLATE mode, air bypasses the chamber and flows directly into your tire like a standard pump. - Integrated aluminum air chamber can be charged up to 160 psi for fast release when needed - Top mounted gauge conveniently placed and easy to read - Air release button allows dialing in exact air pressure