The Ball
Diameter: Greater than or equal to 1.68 inches (42.67mm).

Weight: Less than or equal to 1.62oz (45.93g).

Max Velocity under test conditions: 250ft/s (76m/s)*. See below.

Number of dimples: normally between 250 and 450, although some have contained more than 500 - infact the record-holder was a ball with 1070 dimples, 414 of which were large(ish) and the remaining 656 were the size of a pinhead.

All brands of golf balls have an even number of dimples, with the exception of the Srixon AD333 - which has - yes you've guessed - 333!

*Canadian Jason Zuback has hit a ball with a launch speed of 204mph (299.2ft/s) - awesome!