Talley Scope Ring Bases are machined from solid bar stock. The double recoil shoulder design of the Talley Base holds your scope with absolute rigidity under severe recoil. The base is checked and rechecked by our quality control manager. This is to ensure the best fit possible for your firearm. This base system is required with either Talley Quick-Detachable or Talley Fixed Rings. Select Talley Signature Rings to complete your purchase.