Build total body strength, coordination and balance with the Body-Solid Resistance Exercise Bands. These heavy-duty resistance bands come in 5 varying resistance levels starting with the yellow which has the least amount of resistance and is a ½ inch thick. The green band measures ¾ inch, red 1 ½ inches, blue 1 ¾ inches, and the black 2 ½ Inches. The thickness of the band is directly related to the amount of resistance the band provides (the thicker the band, the more resistance it has) and each band is 41 inches in length. The BSTB1 and BSTB2 are best used for general conditioning, stretching, physical therapy, jumping, aerobics and for increased resistance towards bicep /triceps exercises. Either band works well for beginners and novice weightlifters. For stronger bench presses and lower body exercises, the BSTB3 and BSTB4 work well. For obtaining maximum resistance using squats, deadlifts, leg presses and shrugs, the BSTB5 is our top of the line band. No matter what the workout is, Body-Solid Tools Resistance Exercise Bands got you covered.