The 2-part box is for the Mobius "ActionCam" camera, with an attachment point that fits Freewing R/C aircraft weapons pylons. So you can mount the camera on the aircraft.
For underwing attachment, use the version with the mounts on the TOP. For mounting the camera on the top of a surface, use the version with the mounts on the BOTTOM.

Design is by GRATEFULFROG

Please note that a "shim" is needed to keep the camera from moving around inside the box. I used a piece of foam, which can be seen in the picture. Without a shim, the camera is loose and will vibrate.

I also have some pylons which can be used to extend the box from the mounting surface, please check my other things.