'Bandha' yoga belt is made of washable cotton material that will not be deformed by stretching.
What does a yoga belt do?
Your 'Bandha' yoga belt is used as an aid in your yoga poses. For example, when you cannot reach your feet, you can pass them over your feet so that the movement affects the right place, and you can use it as an aid in 'bind' poses where the hands cannot reach each other.