This was Bluffton's largest employer for several decades of the 20th century. It's the Triplett plant on Harmon Road, as the photo states, taken in May 1936.
Today it is a warehouse for Diamond Manufacturing. Several additional photos and enlargements follow:
Here's the assembly plant of Read Rite Meters in 1931. This building was located across from Harmon Field on East College Avenue. It is now a parking lot.