Williams™ Aperture Regular 1" Diameter (Target) with .050 Hole
Williams™ Aperture Regular 1" 49891 are designed to be used on Williams™ Redfield and Lyman receiver sights. The Williams™ Aperture Regular 1" 49891 creates a sharp contrast that gives quick definition to the aperture. It is important to note the following when choosing the correct Aperture for your sight:
The fractional dimension is the outside diameter of the metal aperture.
The decimal dimension is the size of the hole drilled in the aperture used to aim.