Hydrofix Hydrostatic Release Kit Product No.: 9490 Model No.: HRU-100 ACR Electronics, the world leader in safety and survival technology since 1956, proudly introduces the HydroFix™ Hydrostatic Release Unit (HRU) to compliment our flagship Category 1 Emergency Positioning Radio Beacons (EPIRB). ACR has designed a patent pending release rod system, which does not depend on a battery, sharp blade, or a pyrotechnic device to release the beacon. This advantage allows ACR to offer an HRU that is individually tested to ensure that the HydroFix™ is the most reliable HRU in an emergency situation. All HydroFix™ units are tested to the same high standards and quality workmanship you have come to expect from ACR over the past 50 years. When submerged in water between 5-13 ft. (1.5 - 4 m), the HydroFix™ will disengage the rod allowing the Category 1 bracket to release the EBIRB. ACRs HydroFix™ is now part of the standard replacement kit for the following EPIRBs* and brackets: Model No. Part No. Satellite 406™ (Closed and Open Face Brackets) RLB-27 2754 / 2756 / 2772 Satellite2406™ RLB-32 2774 RapidFix™406 RLB-33 2776 GobalFix™406 RLB-35 2742 Sea Shelter™ 9327 Sea Shelter™2 9435 / 9455 *Not for use with RLB-23 406 EPRIB (fully enclosed bracket)