UAV Propellers
"UAV" stands for Unmanned Aerial Vehicles, commonly referred to as drones.  They have been used for a variety of purposes, including target drones, weather information, aerial photography ,etc.  The Northrop KD2R5 is one example with further information here.
Common manufacturers include U.S. Propellers and Sensenich.
Identification:
Usually not difficult to identify as designed for UAV because of their size, but specific application may be difficult to determine.  Sensenich does have a section of its web site devoted to these props and an option to be placed on their mailing list.
 
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