Choose 1 of 6 different resistance levels. Here are the details of all the parameter of the bands we offer: #1 – 15 to 38 Pounds (1/2 ” *4.5mm), #2 – 25 to 65 Pounds (4/5 ” *4.5mm), #3 – 35 to 85 Pounds (1.25 ” *4.5mm), #4 – 50 to 125 Pounds (1.75 ” *4.5mm), #5 – 65 to 175 Pounds (2.5″ *4.5mm), #6 – 85 to 230 Pounds (3.25″ *4.5mm). With the least amount of resistance, these bands can be employed in stretching, jumping and other light exercises including light weightlifting.