Ten-pin bowling Bowling Championships. Ten-pin bowling has an international ranking system, as with many professional individual sports. This ten-pin equivalent is known as the World Ranking Masters and is made of three vast tours: the European, Americas and Asian bowling tours. Other minor tournaments, although major in their respective countries, include Britain's prestigious BTBA Nationals (BTBA National Championships), the Brunswick Ballmaster Open, Brunswick Euro Challenge in Greece, ETBF European Youth Championships, the European Gold Cup and the Mediterranean Challenge Cup. The world's premier amateur event is the WB/WTBA World Championships (World Bowling) which has been running since 1954 and is now held
Ten-pin bowling off center without falling. The pins must show the name and mark of the maker, either "USBC Approved" or "BTBA Approved" and appear uniform. The maximum diameter of the ball is and the circumference of the ball must not be more than , and the ball cannot weigh more than 16 pounds (7.26 kg). Generally, the lightest ball available for use is 6 pounds (2.72 kg). The ball must have a smooth surface over its entire circumference except for holes or indentations used for gripping the ball, holes or indentations made to bring the ball back into compliance with weight-distribution