The SPRI Xertube is the professional’s choice for isolating and toning all major muscle groups. Small, portable rubber resistance bands can be used almost anywhere and are perfect for group classes, personal training, and even travel. Progressive resistance levels make these the perfect tool for people at all levels of fitness/conditioning. Made from heavy-duty high quality tubing to resist tearing and abrasions. Add a door attachment accessory to have a complete home gym on-the-go!! Available in five different color-coded levels from very light to ultra heavy.