The manufacturer produced the backglasses in both crystal glass and Plexiglas.
The manufacturer's flyer indicates both a Standard Model (replay) and an Add-A-Ball Model was available. This could be expected to mean two separate machines were made, where the Standard Model would have an operator option to award either a replay or an extra ball for each high score threshold while the Add-a-Ball Model would award only extra balls. One game pictured here has the replay number wheel removed from its backbox Replay Unit and it appears its backglass replay window has been blacked out somehow. We don't know if this game is supposed to represent the Add-A-Ball Model.
The schematic in our Files section has an operator setting for either 'Replay' or 'Shoot Again' modes.
If anyone is able to provide pictures of a dedicated Add-a-Ball version, please contact us.
