With it's low-profile AeroHead reinforced head, the Thule Circuit takes durability, style and ease of use to the next level. Install in minutes with tool-free universal mounting hardware. Load and lock your bike with the SecureSkewer - quick, easy, and safe. High-wall wheel cradle design along with the ratcheting strap hugs your bike's rear wheel perfectly. D-shaped, low-profile aluminum tray is sleek and resistant to the elements. Fits all Thule Rack Systems, round bars and most factory roof racks. Requires adapter for loading 15mm, 20mm and lefty forks(sold separately).