If my source is correct, this is the SM series Deluxe friction cap fit made between 1949-54. This one came with the box from a seller who is not a pen dealer so I suspect the box is original to the pen.
The pen drew water and then released. It had just a faint bit of blue ink color when I released the lever to empty which makes me think the pen was only factory tested and never used.
Anyway, this is the second one of this color I've found. The other one will be going to my grand daughter Monday filled with Waterman black ink.