Since the larger 60t chain ring I installed had a tendency to catch the bottom of my scrub pants I used a velcro band around the leg to prevent that from happening. After I forgot to put it on on the way home from the grocery store I decided to try and make a chain guard to mount on the bike. I looked at several options with stuff I had in the garage. I hot bent some ABS plastic but that did not work out. Finding some brackets along with a shipping bracket that came with a 3D printer I bent 90 degrees for a mount, I ended up with this.