Ocean Signal ARH100 Automatic Hydostatic Release Housing -- 41331 -- ARH100 Automatic Release Housing is manufactured in a durable and highly UV stable plastic and provide excellent protection of the unit until it is required. ARH100 automatic release housing, containing a hydrostatic release mechanism which automatically deploys the EPIRB if the vessel is sinking Note: IMO regulations require an automatic release housing to be provided for mandatory fitted EPIRB\'s. « less