Contain the same pull forces and progression as Thera-Band latex resistance bands. Ideal for lower extremity, shoulder, neck, core, and back applications. Features and Benefits:Yellow, Red, Green and Blue sequential Thera-Band color scheme for familiar usage and recognition.8", 12", and 18" lay flat lengths to support a broad range of both upper and lower body exercises.Looped bands have the same resistance level per color as a single length of Thera-Band exercise band tied in a loop.Exercise manual supplied along with extensive online database to create customized exercise programs.