These machined solid steel bases create a secure mounting solution. Bases are a building block of an accurate shooting system. Features Include: Properly aligns your scope and anchors it to your gun, Complements nearly any hunting rifle platform, 2-piece design, Strong & lightweight and Reversible style available for long scopes with large bells or for short scopes; allows the front ring to be set 0.850 in. farther forward or rearward. Sell Unit Each.