Help needed in identifying this model engine screw
 

I have a friend who has a business which supplies screws and miniature hardware to our community. They recently discovered a large quantity of this screw in their stock and are stumped as to its application. I would like to help them identify which foreign engine uses an ALLOY SOCKET CAP 3mm x 12mm screw with a .6 pitch. What is the application ?

ENYA , O.S., YS, Thunder Tiger , etc. ???

I thought it might be a screw for the throttle arm.

Realize it's a crap shoot, but perhaps some engine guy out there can help.