Whether you’ve got hand and arm injuries that need some work, or you simply want the firmest handshake in town – this device has got you covered. Called the Gyroscopic Dumbbell and used by NASA astronauts to maintain their upper body conditioning in space, it is able to produce up to 38lbs of torque resistance at up to 13,000rpm – strengthening your wrists, biceps, triceps, all the way up to your deltoids (those muscles around your shoulders).
