We are pleased to offer the excellent ESU LockSound sound decoders, inluding "V3.5", "Micro3.5" and the "Select" model for American prototypes.  The excellent features of ESU-decoders are even more enhanced by the addition of sound functions. That’s made possible through the award-winning LokSound technology.  LokSound decoders are available for various applications, depending on gauge or digital system.  When you order a LokSound V3.5 or Micro 3.5 decoder, we must know the specific sound file that you would like downloaded to the decoder.  Instructions and lists of sound files are included on each type of decoder's catalog page. (Available "Select" models are each listed separately in our catalog.)