"What are these two cylinders on an elevator/lift control panel labeled ABCD?"
A: "Those are for installing locks (normal keys with keyways) to enter areas e.g. floor 13. Keyways are at least 5cm (2″) deep so they needed a way to orient them sideways as the button assemblies are not deep enough. For smaller buildings where those are not needed those are just design elements."
They found many new uses.
#10 at first glance they looked like vacuum packed bats!
Shark eggs look similar to this as well.
This photo is taken in Hvide Sande (white sands) in Denmark
don't care, would have done her upside down, backwards, standing on my head, one arm tied behind my back, fact might have given my left nut for a run at her.