The Ajax Scientific ME210-0020S plastic gear has 20 teeth and fits tightly on a 4mm outside diameter (OD) shaft for use in science experiments and equipment. The gear is made of plastic for light weight and comes in a package of 10 gears.

Ajax Scientific distributes scientific equipment, supplies, and instruments for industrial, research, and educational applications. The company, founded in 1984, is headquartered in Toronto, ON, Canada.