Designed and printed a simple key chain carrier for the magnetic wide angle and macro lens attachment to my smartphone. The macro lens turns your phone into a quite useful EDC microscope, which has a survival potential, IMO.

The original magnetic carrying plate lanyard could not withstand varying forces in my pants' pocket; I almost lost the lens once due to its failure. Also I've noticed that the lens size is close to the split rings' (which I have on both ends of my braided paracord key chain) inner diameter. So, I've decided to exclude another piece dangling from the key ring, but rather embed it right within that ring. Some sanding for smoothing the thing is pending (dark spots are from the attempt to sand the insides with the Dremel's sand band on the rubber mandrel). "Engravings" on the locking piece are the failed attempt to write a text on it (the custom font rendered bad).

See the Gallery. And the 3D model (use mouse to rotate and zoom).