About Shrewd Lens Housing Retainer Ring
Empty lens housing for the Optum scope. This housing fits any lens that is 1.75" in diameter and at least .08" thick. Made from aluminum and anodized for durability. Once a lens is installed the two parts should be locked together using a thread locker. Allows installation of a sunshade on the target side of the lens. Fits both 40mm and 35mm Optum scopes.
