Arm Trainer Home Machine with Hydraulic Chest ExpanderAdjustable Resistance and Strength Training This arm trainer helps turn struggle into steady strength, allowing users to finish sets effectively and get real workouts done anytime. It features four adjustable springs that offer resistance levels ranging from 66 to 88 lbs, enabling users to build up slowly and push past plateaus. Users can further customize the intensity by moving the springs closer or farther apart to change the difficulty level.