Air filter by DT-1, known for its foam technology that offers maximum airflow while maintaining engine protection. DT-1 air filters are available in standard or pre-oiled form. All DT-1 air filters are handmade in Belgium and the USA, made with high-quality dual and triple bonded foam. The pre-oiled filters are coated with biodegradable, fire-resistant filter oil. The Super Seal base eliminates the need for grease and provides excellent sealing.