Sonic Cardan sockets are commonly known as U-joint or universal sockets, or even swivel sockets. These sockets are made from tough Chrome Vanadium steel for strength and resistance against rust and corrosion. Cardan sockets pivot on two hinges allowing 180-degree rotation, giving the capability to access hard-to-reach fasteners. Allows for more flexibility to reach difficult angles and allows for greater torque applications. They can be purchased in just about any size, including 6PT, 12PT, E-Torx, and more. You can even get these for impact wrenches as well. All are covered by the Sonic Tools lifetime warranty.