The National Lacrosse League consists of men’s professional indoor lacrosse or Box Lacrosse teams. While they have a 95 page Official Rule Book, the rule regarding the ball remains a mystery.
SECTION V- EQUIPMENT
Rule 29: THE BALL
APPROVED BALL –
Only balls that have been approved by the NLL are permitted to be used. Specifications are a solid rubber ball measuring 17.75-8 inches in circumference, 2.5 inches in diameter and 5-5.25 ounces. Balls shall be supplied by the home team and given to the Game Officials one (1) hour prior to game time.
Official Rule Book – www.laxpower.com/common/rules.php
Photo – laxworld.com/lacrosse-blog/2013/04/ground-ball-work-stick-protection-and-drills