For over 30 years, DT-1 have been manufacturing high quality air filters and filter covers which is used by both amateur and professional motorsport riders. Air filters from DT-1 is known to be somewhat out of the ordinary and is said to bring that something extra to the track. Now equipped with an extra layer of neoprene these DT-1's filters are made of the best laminated dual-layer foam on the market and provide maximum airflow. The foam also provides stability to the filter and seals to the surface to prevent the folding lip during installation. DT-1's air filters come standard or oiled. Oiled filters are sprayed with flame-retardant biodegradable filter oil of the highest quality. All DT-1's air filters are handmade and produced in Belgium or the United States with distribution across virtually the entire world.