The Fit Simplify Resistance Loop Exercise Bands are made thicker and hence stronger than most similar products on the market. The green (x-Light) band weighs 2-4 lbs (thickness is 0.4 mm), blue (Light) band weighs 6-8 lbs (thickness is 0.60 mm), yellow (Medium) band weighs 10-12 lbs (thickness is 0.80 mm), red (Heavy) band weighs 15 - 20 lbs (thickness is 1.0 mm), and black (x-Heavy) band weighs 25 - 30 lbs (thickness is 1.2 mm). You can also combine multiple bands to find your ideal weight.