Forest Service Lock by Yale

[YALE7750]

I think the key is older than the lock in that listing; I remember reading an old pamphlet printed by Yale & Towne that mentioned the replacement of the old Y&T logo on keys & cylinders with the all-uppercase YALE logo in a square border being sometime around 1904. Various other lock makers copied the logo in a border & ended up being sued by Yale & Towne for trademark infringement. Before that, keys had the Y&T logo and "Yale Paracentric" like the one in the picture. The earliest paracentric keys had the trefoil bow, same as the old "Yale corrugated" versions.
The USFS was established in 1905, which would make that one of the earliest examples of the USFS padlock key. Definitely a cool find.

Thank you all. I found a lock and key for sale on ebay. I'm really interested in the key as it looks to be original and looks really cool. Here is the pic. Any info, ideas, or thoughts would be appreciated. It is being sold with the lock, but as you know I already have the lock with chain where the one on ebay does not have the chain and pin attachment. Bill