WFFB Combi-Meter shoe mount combination rangefinder and light meter with case

Description

This is a WFFB
Combi-Meter shoe mount combination rangefinder and light meter
with case
made in Germany.
One dial is used to determine an exposure using the extinction meter seen through the large window.
The other dial gives focus distance in feet using the rangefinder images seen in the small window.
The moving image is in vertical alignment with the fixed image.
Due to the nature of rangefinder construction, close distance readings (less than 20 feet) are more accurate.
I did check it at distances of 6 to 22 feet.
The body of the device is cast aluminum with black enamel paint.
The case is solid with slight surface wear.
Length is 2.25 inches.