Helps reduce rope recoil and provide some deflection in the case of an overloaded rope being snapped back into the boat. It is also great for protecting inboard motor boxes from rope wear too.
It is important to note that no product can completely stop the recoil of rope from a fallen skier who has overloaded the line. There is always a certain degree of risk associated with towing a skier who can potentially overload the tow rope and cause recoil of both the rope and the handle. Also, this shock tube will not prevent the handle from recoiling into the boat in extreme cases.