I picked up this business card holder obivously made for Ball watch company.

Here is the back and what makes it a little odd for me. It is marked for the Order of Railway Conductors and St. Louis 1916. Anyone know what this is in regards to?

Here is the inside.

The Order of Railway Conductors had their annual convention in St. Louis in May 1916, at least that is what I found on the web. I believe I have read other posts of Larry's where he mentions holders like those being handed out at conventions.