動く折り紙「すいすいエイ」Action Origami “Swimming Ray”

動かして遊べる折り紙シリーズ。
折り紙エイがヒレを動かしながら優雅に泳ぎます。
How to make an origami ray which you can move. As you push two parts behind, this origami ray moves its fins as if it were swimming!
@Isamu Sasagawa