“It’s a spiral carved into metal, attached to a mechanism that might not look out of place in a junk drawer,” the New York Times reports. “But this humble component, called a precision ball screw, is essential to producing Patriot missiles, airplanes and humanoid robots.”

As the Trump administration works to replace or upgrade weapons systems depleted by the war in Iran, these screws are in short supply, adding months or even years to the time it takes to make a missile.

Ball screws, which contain recirculating balls that reduce friction, turn rotary motion into linear motion, like a corkscrew. While those made for common industrial purposes are readily available, the ones that go into missiles often take a year to produce and can cost more than $1,000 apiece.

“It has created a choke point,” said Nick Kolar, executive sales VP for Umbragroup, an Italian ball screw maker with a factory in Saginaw, MI. He estimated that demand has increased as much as 50% since 2020.

Only a few companies can manufacture these screws for the U.S. military. Most are already at capacity, so it will take time and investment to produce the number of screws required for the weapons the Trump administration wants.

In August, Raytheon announced that it had won a contract to increase annual production of Tomahawk cruise missiles to 1,000 from fewer than 90. Kolar said it would take time and a lot of investment for suppliers to be able to deliver enough ball screws.

“(Customers) need parts in 12 weeks to support the ramp-up for Raytheon,” he said. “We can’t do that. It’s a new design to us. We’re looking at a year.”