The zipper pull of one of my favorite jackets went missing. Although there are a number of excellent designs available using paper clips, I wanted to make one using a nylon zip tie because a) I like using zip-ties, and b) I like the ring of it "zip-tie zipper pull" (appropriate, right?).
This one is one piece and prints fine in PLA with 0.2 layer height with no supports. It uses a small zip tie, (about 1mm thick, 2.5mm wide for the "strap" part).
After printing, use pliers to bend the zip tie at 90 degree angle, as close to the "head" as possible (as shown in the picture). Insert the strap in the sidechannel, loop around the zipper carriage, up the center channel. Should be pretty self-explanatory