Rattleback Puzzle

I own what I thought was a normal, regular size rattleback, and wanted to get a few more for some friends. The price seemed too good to be true.... and I was right! These little things are tiny. I went back to look at the ad to see what I missed, but the only miss about the ad is the part where it is mis-leading. No dimensions are given, no photo of this item next to, say, a quarter coin. I never would have bought these if I knew just how tiny they are. Amazingly, they do perform as rattlebacks should, but not nearly as satisfying to spin a tiny needle instead of spinning a cigar. Sorry, just not the same.

Can't believe I paid for a piece of plastic junk!

Love this demo for my dynamics class