Brief Description: Trailer hitch pins for wing bolts
Per Sonex's most recent wing install instructions, Sonex is using trailer hitch pins as wing attach bolts instead of "bolts." The photos below show the pins. Nice thing is they are pointed to make them easier to insert, plus the clips are easier than a nut, and finally these ones come with handles, making removal easier.
There is a little gap between the pin and the spar tunnel, so that can be filled with some washers.
The cable is used on a trailer hitch to keep the clip with the pin, but with a spar box than won't work. However, figure if I make an attach point on the spar tunnel I can fasten the cable to that attach point and the pins will always be with the fuselage and not get lost.
These particular 3/8" x 4-3/8" pins are from Grainger:
