This is the pinion on the papertransport accessible through the back of the printer. This gear is known to break. Sometimes it can be fixed with superglue, other times it can not. Then this gear can be put in place without disassembling the printer. Fix it in place with a drop of super glue.
The gears fit is not super important as the movement of the paper is controlled by an optical encoder.
Compatible printers are most of the Photosmart 363 cartridge 6 color printers
The author marked this model as their own original creation.