APPENDIX III The Ball 138
1. General
The ball must not be substantially different from the traditional
and customary form and make. The material and construction
of the ball must not be contrary to the purpose and intent
of the Rules.
2. Weight
The weight of the ball must not be greater than 1.620 ounces
avoirdupois (45.93 gm).
3. Size
The diameter of the ball must not be less than 1.680 inches
(42.67 mm). This specification will be satisfied if, under its own
weight, a ball falls through a 1.680 inches diameter ring gauge
in fewer than 25 out of 100 randomly selected positions, the
test being carried out at a temperature of 23 + 1°C.
4. Spherical Symmetry
The ball must not be designed, manufactured or intentionally
modified to have properties which differ from those of a spherically
symmetrical ball.
5. Initial Velocity
The initial velocity of the ball must not exceed the limit
specified (test on file) when measured on apparatus approved
by the USGA.
6. Overall Distance Standard
The combined carry and roll of the ball, when tested on apparatus
approved by the United States Golf Association, must
not exceed the distance specified under the conditions set
forth in the Overall Distance Standard for golf balls on file
with the USGA.
