Xpeed Power Bands Build a better body with the Xpeed two-tone Power Bands. The training guide included will help you strengthen and tone muscles whilst improving your coordination, mobility, acceleration, and power. Power Bands add resistance in the eccentric part of an exercise and during the entire concentric part of the movement. Which means they can be used to alter the strength curve of a movement. They are also able to adapt to complex movement patterns which makes them an essential portable training tool for the athlete looking for complete muscle stimulation. These Power Bands are made of quality material featuring continuous layers of tough rubber which add a level of resilience and sturdiness to make the bands last longer. The thicker the band, the more assistance it gives for pull-ups, chins ups, bar muscle-ups, and ring dips. As your skills improve, you can lessen the resistance level. Conversely, the thicker the band the more resistance you will encounter on powerlifting, squats, and strength exercises. In addition to the above, Power Bands are also powerful rehabilitation and pre-habilitation training aids for stretching and mobility work. Avoid storing in direct sunlight, leaving exposed in a car, or using on or around sharp surfaces. This product cannot be sent to a PO Box, Locked Bag or Parcel Locker.