Summary of what the article is about: > The good where 3D printing is most common is hearing aids. Nearly 100 percent of all hearing aids consumed in the world

Summary of what the article is about: > The good where 3D printing is most common is hearing aids. Nearly 100 percent of all hearing aids consumed in the world are produced using 3D printing.33D printers transformed the hearing aid industry in less than 500 days in the mid-2000s, which makes this product a unique natural experiment to assess the trade effects of this technology. In particular, we use the example of hearing aids to examine the effects of 3D printing on international trade and to study how trade patterns have changed as production technologies shifted. Spoiler: 3D printing of hearing aids increased trade.