SPRI Xertube Resistance Band Exercise Step Cords Green (Light) Beginner/Moderately Fit -- Red (Medium) Moderately Fit/Fit Blue (Heavy) Fit/Very Fit -- Purple (Very Heavy) Very Fit For use with exercise step platforms - rubber sleeve protects tube from abrasive surfaces Step Tube (Light) = 53 in length / Medium, Heavy and Ultra Heavy = 57 in length Includes workout instruction sheet