Stabilizers reduce rolling or pitching of moored or anchored boats by 50%. Pass 3/8" nylon rope (sold separately) through Rocker Stoppers, spacing at equal intervals; connect weights-like small mushroom anchors or salmon weights (sold separately)-to the bottom of each line; and attach the lines amidships on each side of your boat. Made of lightweight, high-impact, virtually indestructible orange styrene. Nests for compact storage. The top of the Rocker Stopper attaches to the boom, whisker pole, outriggers, etc. with 3/8'' nylon rope (not included).