A nursing apron for a breastfeeding mother is disclosed. The pouch is made from a wrapper material having an inner film layer and at least one fibrous material outer layer having a tactile cloth-like softness as compared to the film layer. In the absence of the appliance, at least two of the terminals can be short circuited. A gate circuit combines the first and second fractionally-divided frequencies to provide a transmit or receive frequency with an adjustable duty cycle dependant upon the predetermined time period. If one of input electric signals Si with frequencies fl corresponding to the interdigital periodicities Pi, respectively, is applied to the input IDT, a SAW is excited in the first piezoelectric substrate. When the holding mechanism is outside the treating tank and the first lid member is closed, the second lid member closes an area above the insert opening, and forms lateral openings.