(From the ABC/WIBC Rule Book)
Rule 118d. If because of injury or disability a bowler finds it necessary to change delivery from right to left-handed or vice versa, the league's board of directors, by majority vote, may permit the bowler to change delivery. If approval is obtained, the bowler must establish a new average. A bowler may also obtain permission to alterante delivery, due to injury or disability, in accordance with the provisions of Rule 4c.
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Rule 4c. A player may, if granted permission by the ABC/WIBC and each league or tournament in which the player participates, alternate right/left-handed delivery and/or use special equipment to aid in the grasping and delivering the ball.
The aid cannot incorporate a mechanical device with moving parts that would impart force or impetus to the ball.
Permission may be granted by WIBC/ABC if the following is submitted:
1. A doctor's certificate is furnished to WIBC/ABC, describing the disability and the reason to alternate right/left-handed delivery and/or recommending the aid.
2. A description, drawing or model of the aid (only for mechanical aid).
When authorization is given, ABC or WIBC will provide the player with a special cardstating that alternating right/left-handed delivery and/or the use of the specified mechanical aid has been approved by WIBC/ABC. If permission is not granted, the player has the right to appeal to the WIBC or ABC Legal Committee. Permission may be withdrawn for cause.
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White Dot 
Queen of the Stone 8 Pin
