Hood release cable
But yours is easily fixable. All you need to do is slide the cable end out of the latch mechanism (rusty part at the bottom), and then super glue that black end cap back onto the hex adjuster piece. I'd suggest a gel-type super glue. Just try to avoid getting too much on the cable itself.
The black disc part you're gluing back on isn't under a lot of load normally, all it does is locate the hex adjuster properly in that slot where it presses against the latch. That hex part is loaded in compression when you open the hood latch, it doesn't get loaded in tension with any great force.













