What is this[nail-like thing]? --edited title

In My Humble Opinion
21

Nerds!

22

For mysterious strange grid balls, the twist is on the inside.

23

An update…

The contest is over, by the way.

24

But only partially cast.

25

I think it’s a locksmith’s tool for extracting broken keys.
compare:

Keysplease - Broken-Key-Extractor-(per-unit)
http://www.clksupplies.com/shop/images/DCP_1173.JPG