According to the book All About Pinball, 'Paradise' and its Add-a-ball version Gottlieb's 1965 'Pleasure Isle' were the first playfields designed to have flipper return lanes, which are wireforms that allow the ball to roll behind the slingshot and towards a waiting flipper. However, Gottlieb rescheduled the production of a subsequent game designed with return lanes, Gottlieb's 1965 'Bank-A-Ball', so that it could be released first.
