This is the US Synchro model of the Kodak Brownie Reflex, which was manufactured from 1941 to 1952 and originally sold for $6. Here’s a link to the manual:
Model: Brownie Reflex
Type: Pseudo-TLR
Shutter Speed: I (instantaneous), 1/30 sec, and B (bulb)
Shutter: Rotary
Lens: Meniscus, non-focusing
Aperture: fixed
Film: 127
Picture size: 4×4 cm
Exposures Per Roll: 12
Designer: Henry O. Drotning
Place of Production: US & UK
Dates of US Production: May 1940 – May 1952, Synchro model released Sept 1941
Dates of UK Production: 1946 – May 1960
Other Features: Folding hood main lens and a second-surface keystone reflecting mirror viewfinder, Bakelite body, Original Price $6
The design was patented in 1940 by Henry O. Drotning (US Patent D119931).