As wonderful as the Game Ready therapy system is, just like other mechanical items, parts can break down over time. That includes the O-rings that are part of the Game Ready Hoses. Eventually the rubber O-rings used at all the hose connections will need to be replaced. Over time, as rubber does, the O-rings may swell, crack, rot, harden or otherwise degrade. A problem will be noticed when the unit starts having issues with leakage, difficulty in connecting a hose, certain error codes appear, etc. If hardening is the issue, a little silicone spray (available separately) to lubricate might solve the problem. If not, this kit is here. It includes 10 O-rings and a Utility Packing Hook tool. Before work starts on replacing O-rings, ensure the Game Ready Hose is unconnected to everything. Users should never do mechanical work on a hose still connected to the control unit. Using the tool, gently remove the damaged O-ring being careful not to scratch the metal connector. Replace with a new-O-ring and use the tool to carefully secure it in place, being sure not to over-stretch or twist the O-ring. Work is done when the O-ring is secure 360 degrees in the groove. The tool features a sure-grip aluminum handle and a steel shaft with a magnetic pick-up in the handle. Please note, this is the Hose O-Ring Replacement Kit Only. Game Ready wraps, control unit, hoses and all other accessories are available separately. If unsure if the O-ring should be replaced, try a little silicon spray first to see if that resolves the issue. Replacing the O-ring, while not overtly complicated, does requires some basic mechanical "do it yourself" skills and a comfort level working with tools. The tip of the tool is extremely sharp, so users are cautioned to be careful. Not just for O-Rings, the included tool is terrific for prying open stuck gaskets as well as the removal of springs, washers and waddings. This O-Ring Replacement Kit is applicable to all Game Ready systems.