The Primal Strength Plate-Loading ISO Lever Machines have been engineered to work in the natural motion of the body in order to optimise the isolation of the intended muscle groups. The Machines converge and diverge in a natural, arcing motion, guaranteeing users the maximum muscle contraction whilst providing the safety of a machine to maximise both the benefit and security for users when training. ISO Lever Plate-Loaded Machines have many benefits, including: Independent movement of each machine arm Converging or diverging range of motion Safely isolating muscle groups Maximise weight used whilst applying a natural lifting motion The Alpha Commercial Fitness Elite ISO Shoulder Press offers a natural and very 'true' pressing motion. Simply add the weights required, adjust the seat height and you can utilise the machine for a range of shoulder pressing exercises. As all Primal Strength ISO Machines have single levers, you can train using one arm or both to isolate the shoulder muscles.