When you need to carry a bike on your roof racks, but the distance between your roof racks is greater then 34.4 inches, then a 2-piece carrier is ideal. The RBC012 comes with the same securing features as the RBC011, however the carrier comes in 2 pieces. Suited to fit to Rhino Aero crossbars. Includes RKLS Rhino Key locking Skewer. The key locking skewer allows you to securely key lock your bike to your bike carrier.