The Harbinger Pro Knee Wraps are to support your knees and give you an extra spring while you are doing a lift such as the squat. When wraped tightly and properly (two people can do this much easier then one) you can not wear them for long or else blood flow will stop. Use these for maxes and the such. When you get down into your squat, it helps your knees not buckle and gives them a spring to help get the weight back up. Also supports your knees from injury but don't train with them all of the time or else you will not develop the muscles in your knees to do the other movements.
These are very nicely constructed and very sturdy, I have no complaints with them and they do absolutely what they are made to do, I recommend them to any budding weight lifter!