It is the direct replacement for the AP9012B-6 part number

FFRT: Provides rapid flame failure response to meet strict safety protocols and technical specifications

While physically compatible with many shells

protecting the sensing element from high-pressure flow while maintaining a tight thermal coupling for accurate RTD sensor feedback

Nordyne 921733 Tube Kit 322057-301 It is the direct replacementThe Nordyne 921733 Tube Kit is a critical OEM HVAC replacement part engineered for exact compatibility with residential and commercial air handling and condensing units. As a veteran grade HVAC technician kit, this assembly eliminates the need for field fabricated piping, ensuring that refrigerant line connections maintain factory spec flow rates and pressure tolerances. Whether you are performing a mid season repair or a full system overhaul,