HydroFix™ Hydrostatic Release Unit for Category I EPIRBA rod system does not rely on a battery, blade or pyrotechnic device to release the beacon. This advantage allows for a quick, seamless and reliable release in an emergency. Note that this is a date-stamped product and must be replaced every 2 years from the date of installation or 4 years from the date of manufacture.Features:Allows release of a beacon from a Category I bracket when submerged in water between 4.9' - 13.1' (1.5 - 4 m)Easily replaceable100% factory testedFits: Open Face™, Sea Shelter™ Sea Shelter™2 and Sea Shelter™3 bracketsSize: 2.5" x 3.4" x 2.0" (6.3 x 8.6 x 5.0 cm)Weight: 3.3oz (93.6 g)*Not for use with the following outdated EPIRBS: 2754,2756,2758, and 2759