This is a Digitrax SDXN167N18 Plug-in Next18 connector Sound Decoder for Atlas N FA-1

• 8 CV-Selectable Steam & Diesel Sound Schemes Included
  
• Mobile Decoder with SoundFX v3
• Fits Atlas N FA-1 locomotive and others
• Plug-in Next18 connector
• Motor drive at connector capacity
• 6 FX3 Functions
• New sound .spjs loadable with Digitrax USB programmer