Designed with a slippery JetFlow teardrop shape, the Yakima JetStream Base Rack Bars deliver aerodynamic efficiency, robust carrying performance, and quiet travel at highway speeds. Part of the new Streamline System, the JetStream Base Rack Bars mount to Yakima's Timberline, Ridgeline, and Skyline Towers (sold separately). The JetStream Base Rack Bars include two crossbars and four endcaps.