The DS28RND-8, this is a 2 watt 28mm round speaker, an excellent drop in replacement for the Athearn HO scale SD70ACe and Kato HO scale AC4400CW (Fuel Tank).
The DSM-8 speaker is a perfect fit for the Intermountain HO Scale GEVO.
These speakers are self contained (sealed) and ported. The port allows just enough air to reach the back of the speaker to give a better bass response than standard speakers. .
The Speakers come in two sizes the wide one will fit in HO scale cab units, S scale and O scale engines. The narrow speaker will fit into HO scale width hood units.