Vintage WCM metal awning operator is used on awning windows, possibly some types of jalousie windows. 
Markings: 40-820R

Measurements (2nd image):
Housing: 1-1/16 inches x 1-1/4 inches
Housing Height: 5-3/16 inches
Arm Length, fully extended: 5-1/4 inches
Crank: 3/8 inch Hex

Priced and sold each.
No returns, refunds, or exchanges.