Bushnell laser rangefinders are also required equipment for the avid golfer. They are accurate to within a yard, and can measure distances of up to 1000 yards. The typical use of the rangefinder is for a scoring shot from 200 yards in, to determine the proper club to hit with. Many golf courses have very inaccurate 100, 150, and 200 yard markers. Relying on them will make you mad when your shot goes short or long. Yes, they're disallowed in tournament play. This really doesn't make sense, since pro golfers have extremely accurate yardage books that perform exactly the same task.