A 3:1 zoom ratio is very common in many scope models. It gives you 3 times more magnification at high power than at low power (model magnification ranges are available in powers of 3x: 1.5-5, 2.5-8, 3-9, 3.5-10, etc.), so you can dial your power down for close encounters or all of the way up for long-range shots. Leupold's Custom Dial System (CDS) gives you the ability to customize your turret (adjustment dial) to your exact ballistics and environmental conditions. Once your new custom dial is installed, simply range the target, turn the dial to that number, and aim dead on. A traditional eyepiece lock ring allows you to lock in a focus setting that is best for your eye. Leupold’s Advanced Optical System offers tried and true light transmission for extended glassing sessions, best in class glare reduction in harsh light, and the resolution and clarity that recreational sportsmen and sportswomen demand.