Twin Air (177764 150mm x 50mm Oval Air Box Vent Twin Air's vent system opens the way for maximum airflow, while the fine-toothed GP filter cover protects your engine from dirt and debris The unique two-piece design installs in a snap, with a foam seal that ensures a leak-proof fit Includes a black outer cover to close off the vents during extremely wet conditions Each oval 150 millimeter X 50 millimeter kit comes with 2 vents and 2 caps This product is ideal for engines that are looking for more air