Large Oval Speaker is a good plastic frame oval, 8 ohm 1 Watt speaker for HO & larger scales. It measures 1.11 inches wide, 1.57 inches long, and .457" high, or 40mm long, 28mm wide, and 11.6 mm high. You could be shipped a Soundtraxx speaker or an American Hobby speaker, since they are all the same speaker.