The DualShock 4 is getting a new peripheral called the Back Button Attachment. The device adds a pair of programmable paddles to the back of the controller.
The Back Button Attachment is compatible with the standard PlayStation 4 controller and it will be available January 23, 2020 for $29.99.
The device includes three buttons in total. Two function like the other buttons on the controller. The third is is part of an OLED screen, and you use it to program the buttons and cycle through three different profile modes.
Besides the buttons, it connects at the small port on the bottom of the DualShock 4, and includes a pass through for the headphone jack.
Paddles are additional or alternate locations for buttons, they are rather helpful for those with disabilities, with repetitive stress injuries, or competitive players to improve their response time.