E-flite Brio 10 ARF - Manual (Page 22)

 3. Slide a #4 washer onto a 4-40 x 1/2" socket
head screw. Slide the remaining wing panel into
position. Secure the panels using 4-40 x 1/2"
socket head screws with #4 washers (silver) using
a 3/32" hex wrench.
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