This clip is a descendant of http://www.thingiverse.com/thing:500039 and started out as a curious experiment. This is a "lighter duty" version of the clip.

Here were my goals and challenge.

1. Make a wider clip than 50mm.
2. Use less plastic than the 50mm clip (on thing 500039).
3. Design so no supports are needed.
4. Include some space in clip for bag roll.

Designed to print just like you see it, standing up on the table. Added a small easy break-away tab to aid hold the weight of clip until the middle circle connects.

PLA, using hairspray on glass to get it to stand on its end as pictured.