It's all balls

When you launch a new golf ball, you should submit samples to the governing bodies; USGA & R&A, for them to test whether your golf ball conforms to the latest rules and regulations.
Naturally they do not do this for free, you have to forward a juicy cheque to accompany your samples. Your balls are weighed and measured, plus an initial velocity test is performed for compliance. If successful, your new golf ball can then be included on the list of conforming golf balls. This also allows you to state on your packaging that this golf ball conforms with USGA and R&A rules.
However, there should be an expiry date too. You need to make additional payments every six months or more to the governing bodies to keep your golf ball on the list. A nice little earner for the rule makers to pay for their lunches and new blazers, should they spill gravy down their lapels. Even though your golf ball conforms, without further payments your golf ball is dropped from the list, though your packaging will probably still state conforms to USGA and R&A rules. Does any of this matter? Well, Professional golf tournaments usually insist that players must use golf balls which are on the current list of conforming balls. Strictly speaking these are the only legal golf balls. Though it is up to individual tournaments and golf clubs to decide whether to enforce the list. I suspect that most golfers entering their local club competitions can play with anything.