The CanDo Therapy Propeller is a unique exerciser and a groundbreaker in the world of upper body and upper arm rehabilitation. Designed to improve range-of-motion, aid rehabilitation and improve conditioning and flexibility, this handheld mobility exerciser is versatile beyond belief. The lightweight aluminum design allows the propeller to be portable, adjustable and be used with one-hand or two. For a one-armed workout, you only need to use the base crank. For two-handed use, connect the support crank as the unit can be set up as a traditional pedal configuration or in a U-shape. Adjustable grip resistance dials on each crank allow for an increased or decreased level of difficulty and a workout personalized for the specific user. Multiple resistances, planes of movement and allowing a full range of motion make this one the most complete exercisers available. The propeller is terrific for improving overall fitness, strengthening the grip and improving shoulder, arm and wrist mobility. While designed to be used alone, it easily accommodates assistance, if needed. Comes with a fully illustrated instruction manual. Lightweight at only 1.5 lbs. and compact, the Therapy Propeller easily travels, making fitness on the go a breeze. Use it outside at the park or beach or use it indoors at the office or watching TV. Hand tightening is recommended for all knobs. Do not overtighten and do not use pliers or grippers. The propeller also helps increase flexibility in the elbows and wrists. Allowing for workouts nearly anywhere and anytime, the propeller can be operated from a lying, standing or seated position. Easy to clean with just a damp cloth and mild soap.