BMC Air Filter ACCDASP-13S Performance Carbon Dynamic Airbox. Item has been opened and is in the original retail packaging. Item shows virtually no signs of wear.Item has been professionally tested and inspected to ensure complete functionality. In general, vehicles such as cars or motorcycles require a total particle filtration efficiency of up to a minimum size of 10 microns, to avoid any risk of passage of foreign objects that may damage the mechanical components downstream of the intake system (Air Flow Sensor, injectors, valves and segments). OEM air filters are made of paper and their main function is to protect the engine. These filters have high resistance to the airflow, which reduces the inlet pressure and reduces the engine's performance. BMC's air filters provide a considerably greater airflow. Furthermore, compared to a conventional paper filter, which at the time of maintenance must be replaced, the BMC air filter (being reusable) has a life equal to that of the vehicle itself. Another type of air filter on the market are synthetic filters, which BMC has produced for years only for non-road applications. The main difference between the BMC oiled cotton filters and filters made of synthetic material (for example plastic canvas) is the principle of impurities stoppage. The synthetics allow passage of particles in the size of the micro-filter material: it follows that a filter with 80-micron holes allows the passage of all items below that size, stopping only particles larger than the size of the hole (an example: the sand has a size of about 50 microns). The cotton has a larger plot, which favors the passage of a large flow of air and through the combination of different layers containing oil, ensures the stoppage of all the impurities from 7 microns up. To date, this concept is the best solution for both better filtration and higher performance. BMC Filters are constructed using a process called "Full Moulding" developed by the BMC F1 R&D team. BMC air filters are designed and produced to ensure a higher air flow than OEM air filters. The filtering material is composed of a special cotton gauze soaked with low-viscosity oil to give you the best air permeability. BMC Air Filters are washable and reusable, perfect for high-performance applications.