Drive in certainty with our UNIVERSAL CAR PHONE HOLDER. Easy to install, simply attach the bracket to the rear view mirror. Equipped with sturdy lock knobs which lock to the neck of the mount for sturdiness. The clamp firmly screws onto the rearview mirror giving you exceptional results. The rear view mirror firmly holds devices up to 3.5 inches in width, expands to accommodate large phones such as the iPhone 7 Plus and Galaxy S8 Plus.