What is Retractable Rat Guard? Retractable Rat Guard is a premium, improved rat guard for the mooring lines of large commercial vessels, designed to be deployed and stowed while remaining secured to the line. Rat guards are often required on ships, but ordinary designs often get broken or lost every time the ship is docked. Retractable Rat Guard is made of heavy canvas with rigid plastic ribs, and is designed to remain permanently installed on each mooring line. Retractable Rat Guard can fold down while passing through the hawseholes, to be secured and latched down by the crew when the mooring lines are being stowed or deployed. Retractable Rat Guard can then be activated and expanded by pulling a ripcord from the dock or ship.