Smeg SU45MCX1 Instructions For Use Manual page 15

USA
The Advantages of Microwaves

De-freezing, heating or cooking in a microwave oven is quicker than
in a conventional oven;

The vitamins, minerals and nutritional substances in the food are
conserved;

The natural color and aroma of the food are unchanged.
Microwaves pass through china, glass, cardboard or plastic but do
not go through metal. For this reason, metal containers or ones
with metal parts must not be used in a microwave oven.
Microwaves are reflected by metal...
... but go through glass and china...
... and are absorbed by foods.
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