Apple is testing the use of 3D printers to produce the steel chassis used by some of its upcoming smartwatches, according to people with knowledge of the matter, heralding a major change to how the company manufactures products.

The technique would obviate the need to cut large slabs of metal into the product’s shape. That would reduce the time it takes to build devices while also helping the environment by using less material, according to the people, who asked not to be identified because the plan is private.

The new approach has the potential to streamline Apple’s supply chain and kick off a broader shift. If the work with Apple Watches goes to plan, the tech giant will look to expand the process to more products over the next several years, the people said. A spokeswoman for the Cupertino, California-based company declined to comment.