The Air Filter 17801- is a replacement engine air filter for compatible Hino vehicles. It helps clean the air entering the engine by reducing dust, dirt, and other airborne particles before they reach the intake system. This supports smoother combustion, stable engine performance, and routine vehicle maintenance. The existing listing notes a single replacement unit. Always match the part number and vehicle model before installation to ensure proper fitment and reliable service. This makes it a practical choice for routine maintenance when the listed details match the vehicle requirements.