USGA Golf Ball Rules 

Technology and Golf Ball Design:

With the rapid advancement of golf ball technology, there must be a limit to how technologically advanced one can make a golf ball. The USGA has set several guidelines regulating the construction and design of golf balls.
To be recognized and approved by the USGA, a golf ball must meet the following standards:
 
 
Golf Ball Weight:
According to the USGA Rules of Golf, the weight of the golf ball shall not be greater than 1.620 ounces avoirdupois (45.93 gm).
The heavier the ball (to a point) the less it can be slowed downs by air resistance and therefore the further it would tend to fly. Hence the majority of the manufacturers produce golf balls with the maximum allowed weight of 1.620 oz./ 45.93 g.

Golf Ball Size:
According to the USGA Rules of Golf, the diameter of the ball shall not be less than 1.680 inches (42.67 mm).
A smaller golf ball will generally fly further than a larger one given the weight is equal. The reason for this is: having a smaller diameter ball means less air resistance. Moreover, the majority of the manufacturers produce golf balls with the minimal diameter of 1.680 inches / 42.67 mm.

Spherical Symmetry of the Golf Ball:
Golf balls must not be designed, manufactured or intentionally modified to have properties which differ from those of a spherically symmetrical ball.

Golf Ball Initial Velocity:
The initial velocity of the ball must not exceed the limit specified when measured by the USGA.

Golf Ball Overall Distance Standard:
Overall Distance Standard for golf balls is on file with USGA.
For the most part, all balls sold in the United States meet the above criteria and earn a place on a document known as the United States Golf Association (USGA) Conforming List — which includes many hundreds of models of golf balls.