The CURT Echo brake controller manual override button promotes a hands-free driving experience with any CURT Echo brake controller. It synchronizes with the Echo and your smartphone, using Bluetooth. Then, with the press of a button, you can manually activate the trailer brakes, whenever needed. This allows you to use the Echo brake controller for towing even if local laws restrict the use of smartphones while operating a vehicle. With this button, the Echo continues to operate normally, using the Smart Control app. However, instead of using the app interface to manually activate the trailer brakes, the driver uses this Bluetooth button (app must be running for button to operate). It features a long-range Bluetooth signal and is programmable with other Flic applications. The button also takes up very little space on your dash, featuring a diameter of 1-1/8 inches. It comes with a double-sided adhesive pad for immediate installation in your vehicle, and it has a replaceable CR2016 battery with a three-year lifespan.