rsl12's 45 sec mystery #13
 

This item is frequently gently wiggled. Why wiggle it gently? It's made of metal, for crying out loud.

Shake it, shake shake it shake it like a polaroid picture...

A pen?

um, 100% metal.

A baby's rattle?

a key? i know i have to wiggle my key to get into my dorm building

Key is correct!

you dont wiggle keys, you jiggle keys.

i've never wiggled a key in my life.

from merriam-webster:

Wiggle: 1 : to move to and fro with quick jerky or shaking motions : JIGGLE

Jiggle: : to cause to move with quick little jerks or oscillating motions

A prybar or crow bar is wiggled genly when used to dismantle most trim or woodwork...So is a frying pan...or a metal pot or pan while making popcorn...I wiggle a metal wedge into wood for splitting, or a chisle to carve...I might even wiggle a rasp over a peice of wood to smooth an edge...I could even gently wiggle my metal mixer to create the perfect martini...etc. etc.