Mirage deflector 50mm

Seeing these kind of deflectors being real expensive for what they are, I decided to make my own. I ordered some 50mm elastic band (aprox. 2meters) and started designing. One end of the elastic needs to be looped around the center of the buckle (part 3) and stitched together. Then its just weaving the other end of the elastic through/around the other parts, back through the buckle and fold back over once to create enough friction to lock in place. The outer part (part 2) is made for an M4 hex-screw, 5mm free threads so it can lock underneath the head. The innerpart (part 1) is just a bar I will tywrap on the opticsmount, but other, better designs are definitly possible. All (solidworks) designs are uploaded for your convenience.