A piezoelectric substrate is joined to a cover with a support layer
disposed therebetween and with a space maintained therebetween. A
transmission surface acoustic wave filter and a reception surface
acoustic wave filter are disposed on a major surface of the piezoelectric
substrate adjacent to the cover and inside the support layer. External
electrodes are provided on the side of the cover opposite to the side
facing the piezoelectric substrate. The external electrodes include an
antenna terminal electrically connected to the transmission surface
acoustic wave filter and the reception surface acoustic wave filter, a
transmission input terminal electrically connected to the transmission
surface acoustic wave filter, and a reception output terminal
electrically connected to the reception surface acoustic wave filter. A
portion of an interconnection line that electrically connects the
reception surface acoustic wave filter to the antenna terminal is
disposed on the cover.