It’s a..............

[Joe-Dirt]

Made of iron, I’m thinking drawer pull

 

Amazon Forum Fav 👍

Diving for Pleasure and Treasure - Grab it through Amazon!

[GaRebel1861]

That would be my guess as well.

 

[wainzoid]

how about a foot from an old washing machine or refridgerator?

 

[nagant]

I think it's mechanical, i see a screw head next to the nub and maybe a non ferrous plug or sheared screw on the other side. Maybe a retractable shade end?