Our QR mounts allow you to remove and reattach your scope and return to within +/- 1/4 MOA of the original point-of-impact. The patented lever mechanism, machined with precision tolerances, engages the steel base to the ring, pulling it down and forward and locking it into its zero position. You get ease, convenience, and field-proven, repeatable accuracy. This specific model is for a Browning A-Bolt and are a popular choice for muzzle loaders and large caliber rifles.