This gear ring glues on to the big pulley used with the HONDO Garage 50-Dollar Follow Focus. It has a few advantages over the regular gear adapter:
You'll need to glue this on to the large pulley. We've been using superglue with excellent results. Glue the gear onto the flat side of the pulley, not the side where the hub protrudes. Put a ring of superglue all the way around the inside pocket of the gear ring, as well as some on the four support arms that connect to the center hole. Then slip the gear ring over the flange on the flat side of the large pulley. Squeeze it together to spread the glue. Once you're certain that the glue hasn't gotten all over the place, press the gear ring against a flat object and maybe weight it down for a few minutes. We usually wait about an hour before using and haven't had any problems.