Attach the Bicycle Roof Rack to your vehicle's crossbars to easily transport a bike on your vehicle's roof. This roof bike carrier quickly mounts to the front and rear crossbars using anti-skid mounting plates and knobs that secure to the end of screws. The carrier fits crossbars with a maximum overall size of 2.75" W x 1" H. A bike is transported upright on this rack with a support arm and locking bike frame clamp supporting the bike frame and ratcheting wheel straps holding the wheels in place. Velcro straps are also included for extra frame support and to secure the bike's hand brake. The wheel tray is 2.25" at the top and tapers down to .75", so some larger tires may not be suitable for this carrier. The bicycle roof rack has a sturdy yet lightweight aluminum construction and includes a one year warranty.