Thule's Sonic XL Rooftop Box significantly increases the carrying capacity of any vehicle, and with the AeroNose design it reduces drag and wind noise. The angled rear section of the box increases trunk or hatch clearance. For added convenience, the Sonic opens from either side. Thule makes it easy to make sure the box is closed securely and properly with the Sonic's oversize SecureLock latch. This great rooftop box also includes AcuTight mounting hardware that clicks when tight and fits on Thule crossbars (sold separately), plus most after-market and factory-installed racks.