Traditional, popular models. Tremolo-tuned harmonicas are mainly used for folk music. They are easily recognisable by the horizontal division of the air channels. Each channel has two reeds for each note, one pair for blown notes and another pair for drawn ones. These reeds, which are basically identical, are tuned to slightly different frequencies. When played together, this difference causes the characteristic beating of the tremolo sound, a guarantee for a cheerful and merry tone! All models of the Echo Line are playable on one side and have an exciting nice and warm tremolo sound which is well established in the traditional folk music. Unfortunately due to the nature of Harmonicas we are unable to accept returns as once they have been blown (and sucked) they cannot be resold. Of course if the item is faulty then we are able to have the harmonica back for inspection and repair