A king size duvet cover can come with a couple of different options. Usually they are made from linen or cotton, but they can also be found in polyester blends. A duvet cover looks just like a giant pillow case with three sides sewn shut and an opening at the top to slip the duvet itself into. The opening at the top can be sealed in a few different ways. There is a a style that zips across the top, and there is also a style that buttons across the top. There are also some that that use Velcro straps across the top to seal the duvet in. It really is up to the user as to the preferred method of closure.
The original duvets were made in Europe using the feathers of the Eider duck which is known for having insulated feathers. In Europe the beds were made of feather mattresses and the duvet was placed directly on the mattress so in essence the bed was like an envelope of feathers. Today they are used around the world, although the traditional duvets are still favored in many northern European towns. The ones that are used today are filled with silk, wool, polyester and cotton batting. Very rarely will you find a duvet made of feathers gracing an American home. They have taken on more comforter type qualities in the states. Duvets are meant to be used by themselves unlike comforters that are used with sheets and other blankets.
Duvets are very hard to clean (traditional ones) so keeping them clean is very important. A king size duvet cover will help to keep it clean and can easily be cleaned by slipping it off and throwing it in the washing machine. In addition to keeping the duvet itself clean, a cover also adds decorative options. Typically traditional styles are white, so adding a stylized cover can add some color to the room. You will find that these covers are available in many color options with many different patterns. This is a great way to change the décor in the room without having to buy new bed covers.
Any owner of a king sized bed along with a duvet would do well to invest in a king size duvet cover. Leaving the duvet itself without any protection can be dire, especially considering how expensive one can be — even more so if it is filled with down.