I find it interesting that some Hamilton models were one-year-wonders while other models were produced for several years. Some models, like the Boulton were made for decades, in one form or another, and is still made today!
One of the things that could make a model more appealing over the long term was to vary the case material or the dial options. That was definitely the case with the earlier models from the 1920's and '30s.
Different dials was still an option in 1941 and one of the models to feature them was the Lester. It was originally offered with an applied gold numeral dial or with a black numeral dial.