Duckpin bowling Duckpin bowling Duckpin bowling is a variation of 10-pin bowling. The balls used in duckpin bowling are in (12 cm) to 5 in (12.7 cm) in diameter (which is slightly larger than a softball), weigh 3 lb 6 oz (1.5 kg) to 3 lb 12 oz (1.7 kg) each, and lack finger holes. They are thus significantly smaller than those used in ten-pin bowling but are slightly larger and heavier than those used in candlepin bowling. The pins, while arranged in a triangular fashion identical to that used in ten-pin bowling, are shorter, smaller, and lighter than their ten-pin equivalents,
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