A lot depends on your brake controller functioning properly. There are thousands of pounds to be managed and brought to a halt every time you stop your truck and trailer. The CURT trailer brake controller tester box is an advanced safety measure designed specifically for testing the functions of brake control units. A brake controller is a powerful and sophisticated tool, but as with any tool, it is important to inspect it once in a while. The CURT trailer brake controller tester tests the brake activation function of a brake controller by showing the voltage output while braking. It also checks brake light activation, short circuit protection and disconnect notification. The CURT brake controller tester is compatible with time-based and inertia-based trailer brake controllers and is equipped with a quick plug connector to plug into any CURT brake controller. Testing your brake controller unit with the CURT brake controller tester is easy, and does not require the control to be hooked up to your vehicle or trailer. Simply plug the 12V cord into any standard 120V wall socket, hook up your trailer brake controller unit using the quick plug connector, and you are ready to begin. The voltmeter on the brake controller tester box will display the brake control's voltage output to ensure proper braking power for your trailer, and the red brake button on the tester will allow you to check the brake controller's response without actually hooking up your vehicle for towing. The brake controller tester box also features a brake lamp indicator for brake controllers with brake light activation, a short circuit / overload protection button, allowing you to test the brake controller's response to adverse electrical situations, as well as a disconnect test to ensure that your brake controller will properly notify you of a vehicle-trailer disconnect.