The Thule Echelon 518 Bike Rack is a top of the line fork mounted carrier that provides maximum stability and protection with its durable all-metal head and stiff double-wall tray. The Equalized Twin Cam self-adjusting clamp automatically adjusts to fit a variety of fork dropout thicknesses for a secure hold while the precise ergonomic pressure dial optimizes force on dropouts increasing hold, and eliminating damage to fork. Fits Thule rack systems or other round bars. Factory rack compatible with Thule Ride-On Adapter (sold separately).