Hideous Slinky!

A helical spring transfers energy along its length in a longitudinal wave.

Used as radio antennae in the Vietnam war by US soldiers.

More than 300 million sold.

Thanks Wikipedia!

We have two pristine, boxed versions in the prep. room.

A chance discovery this morning!

Drove to work. It took me about twice as long, was twice as stressful but there you go....