 American-style eight-ball arose around 1900.In 1925, the Brunswick-Balke-Collender Company began offering ball sets specifically for the game using seven unnumbered and seven (in contrast to the numbered and found in most pool ball sets), a (numbered "8" or unnumbered), and the white ; these are also known as "casino style" and were introduced to make it easier for spectators to identify the two sets.The ball sets typically range from 2 inches (50.8 mm) up to  inches (56 mm), often with a slightly smaller cue ball, e.g.