Model: L-104 Master
Circa: 1960 - 1973
Cell type: Selenium
Measure type: Reflecting/Averaging
Sekonic licensed the rights to the Weston Master IV and manufactured it in Japan. To the best of my knowledge it was never sold in the USA; yet everything is written in English, so I have no idea where they sold it. Seems to me if it were domestic, it would be marked in Japanese. Except for the badging, it's identical to the Master IV cosmetically. I haven't pulled it apart to see if it's any different under the hood.
Weston's version was in production for only a few years; this one was still being made when the Weston Master V went out of production. I liked the IV better than the V anyway, so it seems like this was a great deal—if you could find one.