Panasonic NN-E221 MM Operating Instructions Manual page 8

 Do not use harsh, abrasive cleaners or sharp
metal scrapers to clean the oven door glass
since they can scratch the surface, which may
result in shattering of the glass.
 This appliance is not intended to be
operated by means of an external timer or
separate remote-control system.
 Only use utensils that are suitable for use in
microwave ovens.
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