Old as Dirt!
While inspecting their equipment preparatory to a passage from Carriacou to Trinadad, friends of ours cruising a sister ship to ours discovered that the adjusting barrel on the ABI Highfield Lever that they use to set up their removable inner forestay had developed significant crevice corrosion. The stock fitting is/was a closed barrel of stainless steel. Upon removing it, the owner discovered that it was nearly full of water and that approximately 2/3 of the barrel was cracked through. Fortunately, he had a open barrel chromed bronze turn buckle in his spares locker that matched the threads. The failure of that fitting while under stay sail and reefed main in the prevailing conditions on that passage would have been very problematic. Anyone relying on that gear would be wise to inspect the adjusting barrel, or better, replace it with an open barrel of bronze. Unfortunately, ABI is no longer in buisness so there's no help there.