This type of bolt placed in a sea cliff is a bomb with a short fuse. Once started, SCC spreads like a disease following the stress lines in the steel, much like grass grows in small cracks in concrete and forces the pieces apart. The cracks get larger over time, and soon the microscopic grains of the metal are no longer in contact. Although SCC can occur on any part of a bolt exposed to salt water, it usually occurs under the hanger where salt water wicks into the crevice between the hanger and the rock surface. Bolts corroded by SCC typically break flush with the surface of the rock.
Hangers typically break at the ninety-degree bend, and nuts can crack just about anywhere.
These have a thin outer cladding of stainless steels urrounding a core of mild steel. These should be an major improvement since they don't have the high levels of stress that expansion bolts have. No one knows how long stainless steel glue-ins will last. We wanted a bolt that could be trusted for over 30 years in this environment. We still couldn't ignore the more common corrosion mechanisms such as oxidation, galvanic and chemical corrosion.