With the Blue Tees Series 2 Golf Rangefinder in your bag, you'll know exactly which club to choose. The Series 2 will measure the distance to a flag up to 800 yards away to within one yard and issue a vibrating pulse so you'll know you're locked on target. Because it has no slope-measuring capability, the device conforms with USGA rules for tournament play. The EZ Optic Focus HD display gives you a clear readout of the distance. The rangefinder is powered by two included CR2 batteries.