Leupold® steel Standard (STD) rings and bases are the most versatile of all mounting systems we offer. This specific ring model fits any scope with a 30mm main tube and is intended to be paired with Leupold STD bases. It is the perfect choice for calibers smaller than .300 Win. Mag. STD rings come in five different heights and are precision engineered to match up with STD 1-piece or 2-piece bases. The front dovetail swivels, allowing for lateral adjustment using the rear window screws while aiming. Nothing is more crucial than the link between the scope and the firearm. Therefore, Leupold mounts are as robust and reliable as the Leupold optics they secure. And with a wide variety of mounting systems to choose from, you're sure to find the perfect match for your firearm and shooting style. Made in the USA and guaranteed to last a lifetime of abuse, Leupold mounts will never let you down.