Yale Padlock- interesting key

[Donnie]

Hi Team, I picked up an interesting padlock at the flea mkt. last week.. Interesting to me , that is, because I have not one like it in my collection.. I'm not a big collector of Yale lock's, other than push key types, both conventional & pancake's/// but this keyway caught my eye.....Anyone want to throw some info at me......thanks, Donnie
now to try & get a photo up