Bowling ball random when impacting a full rack of pins on the first delivery of a frame, and sometimes when hitting downed "dead wood" pins on subsequent deliveries—the candlepin bowling sport is the only major one that allows fallen pins, provided no part of any fallen pin extends more than 24 inches (61 cm) forward of the head-pin spot, to remain on the lane's pindeck to be used in knocking down more pins with the next ball delivery in the same round—up to three balls are delivered, much as in duckpins, in each round of candlepins for one bowler. Bowling ball A
Ten-pin bowling Track, DV8, Roto-Grip, Hammer, Circle Athletic, Columbia 300, Dyno-Thane, Fun Balls, Legends, MoRich, Robby, and Via Bowling. Specially designed shoe design and manufacture is also a significant enterprise that many companies have gotten involved in next to ball production. Some of the major shoe designers are Circle, Dexter, Etonic, and Linds. Individual stores that sell the merchandise made by these companies specifically for ten-pin bowlers are called pro shops. In the United States, bowling equipment sales totaled US$215 million in 1997 which is around the same figure as in 1996 when the Sporting Goods Manufacturers Association (SGMA) released their reports.