Assortment of plastic gears for sale. 70 in total.
From the listing
"This is an assortment of plastic/nylon (not sure what they're made of) gears that I've collected over the years. These are mostly from old printers and fax machines that I've stripped for the stepper motors. Please bear in mind that most of these will not mesh with each other - they're all different sizes, pitches, and different centre hole diameters, and many of them have original grease on them. So don't expect to be able to make a large gear train out of these, most of them won't mesh."
The ruler in the picture is 20cm ( 8" ) long