It was a baby shower gift for Archer, although I have to say, for a minute I thought it was for me. Ahem. I believe his is a Carters Caterpillar but I see them around. It works like this: you attach it to something, pull it (to make it longer) and it vibrates back to its original size. Ahem, ahem, ahem.I was a bit apprehensive at first. Albeit pretty darn cute, it's, well... Kind of "adult" in size, shape, action. As long as the kid loves it and it helps him nap during the day I got nothing but love for Mr. Stretchvibracaterpillar thing and totally recommend him to GGC readers.