With the Mark 4HD, Leupold took the legendary performance of its predecessors and gave it a slimmer maintube that's been packed full of professional-grade features. It starts with the Professional-Grade Optical System, delivering unmatched light transmission that's designed to perform in the most challenging conditions. Its industry-leading glare reduction provides a clear image in harsh, direct light. A 3-turn M5C3 dial tops the elevation turret, providing 30 MILs of adjustment in 0.1 MIL increments, and the patented ZeroLock ensures the dial won't move when knocked around. With its first focal plane reticle, 4.5-18x magnification range, and side focus parallax adjustments, engaging at mid-range is just as easy as identifying threats from a distance. And like all Leupold Scopes, the Mark 4HD is 100% waterproof, fogproof, rugged-built, and backed by the Leupold Lifetime Guarantee. More on the PR1-MIL first focal plane reticle Created with input from elite shooters and hunters, the PR1-MIL provides multiple aiming points for extreme long-range shots. With a useful MIL-based grid, you have a wealth of ballistic information at your disposal. And because it's on the first focal plane, the indicator markings are useful at all magnifications. Professional-Grade Optical System offers unmatched light transmission First focal plane Illuminated PR1-MIL reticle Motion Sensor Technology (MST) extends battery life by automatically deactivating illuminated reticles after five minutes 100% waterproof, fogproof and shockproof M5C3 3-turn elevation dial provides 30 MILs of adjustment ZeroLock system eliminates accidental dial movement ZeroStop for easy return to zero 0.1 MIL adjustments for windage and elevation Integrated throw lever Made in USA Backed by the Leupold Lifetime Guarantee Order today!