This is the On30 14-Ton Two-Truck Stearns-Heisler Plug-and-Play Sound Module from Bachmann. Suitable for Ages 14 & Up. FEATURES: Provides prototypical 16-bit Tsunami® sound when plugged into decoder inside Bachmann On30 14-Ton Two-Truck Stearns-Heisler Locomotives Instructions included INCLUDES: One On30 14-Ton Two-Truck Stearns-Heisler Plug-and-Play Sound Module REQUIRES: Installation SPECS: Scale: On30 COMMENTS: Due to small parts that could cause a choking hazard please keep away from children 3 years of age and younger tlc 4/20/12