HHA Sports TE-5519 Optimizer Lite King Pin (Tournament) .019 Sight, Black Crystal clear magnifier and blue burst light allow for rapid adjustment 5 feet of 019" fiber optic Precision machined brass rack and pinion delivers silky smooth operation Sight in at 20 - 60 yards and you are dialed in "to the yard out" to 100 Interchangeable wheels allows for quick changes between multiple arrow or draw weight combinations