The Again Faster Barbell Jack allows you to add plates to a heavily loaded barbell without strain.
Place the lever under one end of the bar, and press down. The barbell will elevate slightly, allowing you to add and remove plates without interference from the ground. When you’re going for a one-rep max, this is a lifesaver. Having several in the gym will speed lifting sessions and aid classroom management, especially when multiple athletes are sharing a single barbell.