The Kenworth W900L with Cummins ISX Engines Lower Coolant Tube is a practical and essential component for Kenworth W900L models with Cummins ISX engines. This natural finish coolant tube is sold individually and fits most Kenworth W900L models with Cummins ISX engines. It is designed to OEM and aftermarket standards, with the OEM and aftermarket numbers being F66-2181. Ensure optimal engine performance and cooling system functionality with this high-quality coolant tube.