The Prusik knot secures a loop of smaller rope or accessory cord to a climbing rope in such a way that it can be slid along the rope, but when it is loaded will bend the rope and hold securely. The knot is commonly tied with accessory cord by a climber to ascend a rope or to secure a belay system in order to release the belayer. To tie a Prusik knot, use the loop of smaller rope to form a girth hitch around the larger rope, then bring the free bend of the loop around the larger rope. Bring the free bend of the loop around the larger rope a second time and pass it back through the other bend. Dress the knot so that it lies neatly on the larger rope, and remove any slack.