Black Mountain Products strength resistance bands are the ideal fitness tool for Crossfit, weight training, assisted pull ups, and much more. Each blue strength band measures 41" and is 1/2" thick, with a resistance ranging from 10-35 lbs. of resistance. Strength bands are perfect for gym, home, traveling, and office use. Each loop resistance band is made from natural rubber to achieve ultimate resistance and durability. Each Black Mountain Products strength loop band comes with a lifetime warranty.