Features: DT-1‘s world-class foam technology delivers maximum airflow while maintaining critical engine protection. DT-1 Air Filters come standard or pre-oiled. All DT-1 Air Filters are handmade manufactured in Belgium and USA with the highest quality bonded dual and triple foam available. The pre-oiled filters are oiled with the highest quality flame resistant bio-degrable filter oil. Their Super Seal base eliminates the need for grease and creates the cleanest and best seal on the market.