The Williams "Fool Proof" (FP) sight has internal micrometer adjustments with positive internal locks. The FP Receiver Sight is strong, rugged, and dependable while providing a large range of windage and elevation adjustments. The alloy used to manufacture this sight has a tensile strength of 85,000 pounds. Yet, the FP Receiver Sight is light and compact, weighing only 1-1/2 ounces. For big game hunting, the FP Receiver Sight will outsell all other makes and models of receiver sights put together. Many rifles are now being drilled and tapped at the factory for installation of the FP Receiver Sight. FeaturesMicro-adjust windage and elevation rear peep sightDesigned to be paired with Williams Western Precision front globe sight but can be paired with a traditional front sight