Originating in Europe, a featherbed is a feather-filled bedding element providing support for the entire body. A featherbed is placed on top of a mattress, either under or over a fitted sheet, to create gentle support. It is made of feathers, encased within a feather-proof fabric shell, and possibly a down top. Construction will be either baffle box, horizontal baffle channel or vertical baffle channel. Shop Pacific Coast® Featherbeds.