They are fun and kids WANT to wear it. Sea Squirts look like fish for a serious reason. Each design has a flexible fin on the back to help kids get carried away with creative play. It"s a brand new idea and there"s nothing like Sea Squirts on earth. * Swimways Sea Squirts Life Jackets are Type III U.S. Coast Guard certified as a Personal Flotation Devices * Fin folds over when leaning back for active use * The arm-hole sizing insures a proper comfortable fit so the strap between the legs doesn"t have to be too tight. * Grab me fin can be used as swimming aid