In my mind, the 5 rivet hole box was introduced to be used with N frame revolvers - 38/44 Outdoorsman and 357 Magnums. It was a riveted picture box made from 1933 to 1941. Also, the 4 rivet hole boxes were made for the K frame Outdoorsman and K22 Masterpiece in the same era. The riveted gold and blue boxes continued after WWII with both frame sizes made.