Your railings and cleats can't take it anymore. Reduce the tension from dock lines to your boat with some Shockles. Rig the Shockles on your dock lines with a quick clove hitch and eliminate the jarring and stress that can lead to loose cleats and strained lines. Shockles can also attach to anchor chains by clipping them to a couple of feet of slack, thus absorbing any shock and nixing annoying noise from the line. Sizes range from 12 to 24 inches. Prices start at $48.95.