Replace Hammar H20E Hydrostatic Release Unit and bolt after two years of service.
Use only manufacturer-approved replacement bolt.
For models:
E3A (SOS Rescue 406a, Sa 406a, Sailor 406a)
G4A (SOS Precision 406A, Sailor GPS 406a)
G5 Smartfind Plus A&M
E5 Smartfind A&M