"J. Stevens purchased Cataract Tool & Optical Co. & in 1902 introduced their line of scopes that remained in production until the scope business was purchased by Lyman.

The 438 was designed in 1911 by the Stevens Co. In 1929 Lyman bought Stevens Arms scope business and this is one of the scopes Stevens made that become the 438 Field. It was a 3x scope till 1937 when they made a 4x. scope features Bausch an Lomb lenses and a 23.0 field of view @100 yards.Mounts were the same as the Lyman 5A till 1932. This series of scopes was discontinued in 1947. Also states that this scope was designed to withstand the recoils of the 1903 springfield rifle and is by no means a "modern scope". 

Lyman’s purchase of Stevens optics in 1929 moved the company from its long history of iron sights and reloading equipment to the field of optics. Conveniently for this story, Stevens had bought Winchester’s optical production not long before. Ultimately, Lyman’s first scopes used Winchester tooling, Stevens designs, and Bausch and Lomb glass, sold under Lyman’s name. Even the venerable Winchester A5 would be reproduced by Lyman under the name 5A."