Leupold BackCountry cross-slot bases are made of 7075-T6 aluminum, making them some of Leupold'slightest and most rugged mounts yet. Nothing is more crucial than the link between your scope and firearm. That's why theirmounts are every bit as rugged and dependable as the Leupold optics they secure. And with a huge variety of mounting systems to choose from, you're sure to find the perfect match for your firearm and style of shooting.