The Add-a-ball version of this game is Gottlieb's 1965 'Flipper Pool'. 'Bank-A-Ball' was the first pinball machine produced with flipper return lanes, which are wireforms that allow the ball to roll behind the slingshot and towards a waiting flipper. According to the book All About Pinball, Paradise and its add-a-ball version Pleasure Isle were the first games designed to have return lanes. However, Gottlieb rescheduled the production of Bank-A-Ball so that it could be released first. Pictured in this listing are Early Production playfields that match the playfield shown in the manufacturer's flyer. The return lane white arrows show the words "Lights Bumpers" in them. Also, the lower playfield shows the 8-ball as an actual illuminating insert. Sometime during production, the words were moved to be below the arrows and the illuminating insert was removed, leaving the 8-ball painted on solid wood. One example we picture shows a certificate with serial number 01072. We know that Sample games do not show the 'S' designation on the certificate but only show it stamped into the wood of the cabinet. It's possible this game is a Sample. The backbox on this game is sufficiently crowded with mechanisms such that there was no room on the back of the insert for the connector jacks to be installed to allow the playfield plugs to connect to them there. Instead, the connectors were placed onto a separate "plug mounting panel" that just hangs down into the cabinet through the access hole between the backbox and the cabinet. Because of this, Gottlieb affixed to the inside bottom of the backbox an Assembly Instructions card to assist the operator with proper placement of this separate panel to allow the insert to be lowered to its service position without obstruction. The example card pictured here is A-9487-1 and was stapled inside a Bank-A-Ball backbox even though the card carries the Model Number 222 for the game that immediately preceded it in production, the 4-player 'Dodge City'.