I happen to have a soft spot for boompers!

 

I think traditionally they were worn by Oomper Loompers.

 

Boomp.

 

Humper

 

Hey now..... Boomper cars are a very popular ride in the northern Midwest.

..... and while we're talking about this subject, that is a funny eBay description. The best for a bumper was "It sounds like a nickle is banging around inside the watch".