The Xbox Adaptive Controller or XAC is an officially licensed controller from Microsoft Xbox. AbleGamers, along with other consultants, helped Xbox come up with this unique controller that has two large buttons and one directional pad along with ports on the back of the controller to plug 3.5 mm switches that can function as any button on a standard Xbox controller.
Essentially, this controller is a hub that allows you to plug in many different custom parts to make a solution that’s more tailored to your situation.