Slinky tango

I came across this interesting description of a spring, known in the market as SLINKY, under the article "Accidental Geniuses" in the Feb 2003 edition of Reader's Digest. The slinky is made of blue-black Swedish steel.

"It was just beautiful. As for its walk, Mae West couldn't do any better. It flipped, paused somewhat coyly - should I or shouldn't I? - then flipped again, wiggled for a second, leaned into a backend and flipped yet again, humming all the way."