HydroFix Hydrostatic Release Unit (HRU)The HydroFix Hydrostatic Release Unit (HRU) is a patented rod system that allows a beacon to be quickly and reliably released from a Category I bracket when submerged in water between 4.9' to 13.1' (1.5 to 4 M.) 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.*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. Compatible With: ACR Sea Shelter, Sea Shelter2 and Sea Shelter3 brackets ; Features: Easily replaceable; 100% factory tested; Technical Specifications: Dimensions - 2.5" x 3.4" x 2.0" (6.3 x 8.6 x 5.0 cm); Weight - 3.3oz (93.6 g); *Sold as an Individual WARNING: This product can expose you to chemicals which are known to the State of California to cause cancer, birth defects or other reproductive harm. For more information go to P65Warnings.ca.gov.This product may not be returned to the original point of purchase. Please contact the manufacturer directly with any issues or concerns. - cis2:mm5mnJlm -Specifications: Type: Parts; Box Dimensions: 3"H x 6"W x 8"L WT: 0.6 lbs; UPC: 791659949016; Owner's Manual (pdf)Brochure (pdf)