This is a plate that goes over the wings securing them to fuselage. I slightly modified design trying to reinforce it as 3D printed part will be weaker than original. Where level should be I have re-purposed this for camera mount, using 1/4" BSW 1/2" long screw.
I would suggest printing this in resistant filament (nylon, taulman alloy910). Also I think it is good to use wide washers under screws to spread out stress as evenly as possible.