All of Apple’s current products use two different kinds of connector types: Lightning, which is found on iPhones, and USB-C, which is used on the new MacBook Pro to attach accessories and charge the laptop.

But Apple recently introduced a third connector in a developer preview for Apple’s accessory makers, according a report from 9to5Mac’s Jordan Kahn.

Apple does not plan to include this new kind of connector on iPhones, iPads, or Macs, a source familiar with Apple’s plans told Business Insider.

The new connector is called the “Ultra Accessory Connector,” the person said. But it’s not a completely new connector – it’s been around for years. It can be found on Nikon cameras, where it is called the UC-E6 port.

The Verge writes that the UAC will be used “as an intermediary” so that headphones can be compatible with both Lighting and USB-C, with additional dongles.

According to 9to5Mac, accessory manufacturers could make additional dongles that allow iPhones to connect to UAC accessories, such as a 3.5mm jack to UAC adapter or a dongle that converts Lightning to UAC.