– 25 years experience in rubber band strength training made by the same factory in Sri Lanka that made the original Jumpstretch Flexbands. – No Bonding, moulding or seams are used. – Bands are built in layers on mandrels with no seams for potential breakage. They are backed by full 1 year warranty. – 41″ long, 1/4″ thick. Train Quick to be Quick – Increasing Speed – Improving Vertical Jump – Alleviating Back Pain – Physical Therapy – Strength Training How to choose your bands Resistance is measured at 72″. For example at 42″, there is no resistance. Resistance progressively increases up to the rated resistance at 72″ Then it will continue to increase above the rating if it is stretched longer.