Davis DockShockle 12"The Davis Instruments DockShockle is a simple and safe solution for reducing dangerous shock loads and minimizing stress on lines. Additionally, the DockShockle reduces chafe, resulting in longer lasting lines. You can use the DockShockle with all types of dock lines up to 3/4" in diameter. For braided or twisted lines, a pair of Mini-Line Grabbers are included for easy attachment. The Davis DockShockle is designed specifically for dock lines for smaller, lighter boats (up to 40 ft in length), but can also be used on towing lines to minimize shock and tie down lines to securely hold items in place.Davis' DockShockle is made of 2500 lbs. test nylon webbing with an outer sheath of 3500 lbs. nylon webbing that's UV resistant to protect all internal parts. The DockShockle stretches to about 5" under 50lbs. of force. The maximum stretch is 7.5" until the Load Limiter engages. The patented Internal Stretch Limiter increase the return force in relation to the amount of stretch. You can easily adjust the amount of stretch by setting the desired amount of slack. Ideal working slack in line is 3 to 6 inches.Specifications: 12" Long webbing; Ideal working slack is 3" - 6".; Included: (1) 12" DockShockle; (2) 316 Stainless steel carabiners; (1) Pair of 7" Mini-Line Grabbers; Use the included Mini-Line Grabbers with the DockShockle to attach double-braided or twisted lines. Mini-Line Grabbers use a constrictor knot called a Prusik Hitch. They will not damage braided or twisted line.