quote:• In PBA Tour competition, clear plugs and solid inserts (slugs) may be used in finger and thumbholes, provided they do not exceed three fourths (3/4) of an inch across the diameter of the hole. When manufactured inserts are used in conjunction with clear plugs or solid inserts, the total thickness cannot exceed three fourths (3/4) of an inch. • In PBA Senior Tour, Regional Tour, PBA Tour Qualifying Round, U.S. Open, and PBA World Championship competition, there will be no specific plug limitations for plugged equipment. However, no foreign matter may be placed in the plug area, and all equipment shall otherwise comply with PBA regulations.