JimTag I found on my Engine

[JamesG]

Hey everyone, I'm new here but browsing thru all the threads I see a whole lot of knowledge. With that, I'm curious if any of ya can decide this tag I found on my Engine. I have no idea what the engine came from or the year. Thanks everyone

 

[JamesG]

Hmmm, no one has ever seen one of these?

 

[General karthief]

Engine rebuilders tag.
google search: http://www.parttarget.com/National-Engine-and-Parts-Co_nsn-parts.html