A flexible, closed loop device that includes at least one indecomposable knot formed that helps define a plurality of adjustable loops. The knot can be easily loosened so that the loop sizes can be adjusted. The knot is easily tightened and locked. In some embodiments, the device includes at least two indecomposable knots. The device is useful in the practice of yoga, Pilates, and other personal training exercises. The device is flexible and easily adjustable, allowing the user to more effectively target specific muscle groups. The device may additionally or alternately be used as a securing and carrying strap for items. Still further, the device may be used as a connecting device to link items together for towing, hoisting, etc.