Rattleback Puzzle

popular scientific novelty, this is a boat shaped piece of plastic that you can spin by flicking one end with your fingertip, so it spins clockwise. Then it stops, and spins back on its own, anti clockwise, in a most intriguing way. It will keep you amazed and amused, and even educate you in Newtonian Physics when you learn how and why it works! These make an extremely affordable giveaway.I use them with the half regular and half all the same card deck