This is the strength trainer that enables you to build and tone muscles while sitting in an office chair. The unit's dual Velcro straps attach to a backrest and the elastic bands and pulley system provide resistance as you perform traditional weightlifting movements. The three included sets of elastic bands interchange to provide four, eight, and 12 pounds of resistance for the more than 20 possible exercises, including bicep curls, shoulder presses, and bench presses. The strength trainer helps relieve muscle tension that accumulates during long periods of sitting and the elastic bands build strength without putting undue stress on joints. Frame is made from durable polyamide and aluminum Accommodates 11 3/4" to 19 2/3" high backrests. Assembly required. Includes a booklet that demonstrates exercises. 25 2/3" W x 25 2/3" H x 3" D. (4 1/2 lbs.)