Apple has started making protective face shields for health workers on the front lines of the coronavirus pandemic.

The tech giant plans to ship more than 1 million see-through shields each week through a “company-wide effort,” CEO Tim Cook said. The first batch was delivered last week to Kaiser hospital facilities in California’s Santa Clara Valley, where they received praise from doctors, Cook said.

“We are closely coordinating with medical professionals and government officials across the US to get these to where they’re needed most urgently,” Cook said in a video posted to Twitter Sunday. “We hope to quickly expand distribution beyond the US.”

Apple put its product designers, engineers, suppliers and operations and packaging teams to work to design, produce and ship the adjustable face shields, according to Cook. They come in boxes of 100 and each one can be assembled in less than two minutes, he said.

The US Centers for Disease Control and Prevention say health workers should wear face shields like Apple’s when they don’t have tighter-fitting face masks — or in combination with homemade masks.

The Cupertino, California-based company has also sourced more than 20 million masks around the world through its supply chain, Cook said. Other big tech firms such as Facebook and Salesforce have also donated masks amid a supply shortage in the US.

“This is a truly global effort and we’re working continuously and closely with governments at all levels to ensure these are donated to places of greatest need,” Cook said.