In addition to the plastic components, the robo shark contains several metal parts including the gearbox axles, fasteners and the weights in the sharks belly. Although the manufacturer’s website states that these components are made of iron, their magnetic properties suggest they are more likely made from steel, coated in zinc.

This is determined from the bright, shiny finish on the parts, a strong indication that a zinc coating is present (Janekits, n.d.).

This coating is likely used to prevent rusting in the parts (A Class Metal Finishers, n.d.) as they are constantly exposed to water when the toy is in use.

These components are likely prefabricated, rather than manufactured specifically for the shark toy. Replacement screws for toys and electronics are commonly available made from zinc coated steel (Amazon, n.d.)