This allows you to run at the regular speeds on the mainline, and switch to much finer control when switching at slow speeds.

Equipment Requirements for Switching Speed

This feature is provided in the decoder. Currently, the only decoders capable of this are Digitrax's new DH163IP and DN163K0A. All new Digitrax decoders with the last digit of "3" will also have this feature.

Other than that, you'll need a way to program the Switching Speed CV to activate it, and you'll need Function 6 control to turn it on and off.