The SPRI Xertube Resistance Band is the ideal workout tool you can use anywhere any time for safe and effective totalbody conditioning. SPRI rubber resistance products are created using a dipped process rather than the more common and inexpensive extruded process making it one of the most durable and reliable tubes on the market! The handle plug protective sleeve and grommet reinforcement features (Tuff Sleeve) also contribute to making SPRI the tubing product that is tough and reliable enough for many of the US military training kits. All SPRI rubber resistance products are made using Tuff Tube a SPRI exclusive. This heavyduty high quality material has greater resistance to abrasion and tears to stand up to the rigorous demands of professional use. Built to a professional grade quality and designed for commercial gyms and clubs to be used 100 times a day versus 100 times a year in a home gym. Perfect for use in group training and strengthconditioning classes Pilates and physical therapy and rehabilitation. Tube Lengths: Very Light/Light 44 Medium 50 Heavy/Ultra Heavy 53 Yellow (Very Light) Xertube is for beginner men and women. At 11/2 times its length the weight equivalence of this tube is approximately 35 pounds. Green (Light) Xertube is for beginner women and moderately fit men. At 11/2 times its length the weight equivalence of this tube is approximately 610 pounds and offers 50Percent more resistance than Very Light (Yellow) Red (Medium) Xertube is for moderately fit women or fit men. At 11/2 times its length the weight equivalence of this tube is approximately 10 pounds and offers 40Percent more resistance than Light (Green). Blue (Heavy) Xertube is for fit men and women. At 1 1/2 times its length the Blue (Heavy) weight equivalence is 15 pounds and offers 42Percent more resistance than Medium (Red). Purple (Ultra Heavy) Xertube is for extremely fit men and women. At 11/2 times its length the weight equivalence of this tube is approximately 2027 pounds and offers 20Percent more resistance than Heavy (Blue). SKU:ADIB0000AJ057