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It is a bit expensive but worth it if you have dust allergy and Asthma. I really like the product. It comes with a zipper to lock the pillow in. It is white in color and I wouldn't prefer washing it often as the cotton threads can loosen up and allow the dust mites to come out. Though the instructions state you can wash it with cold gentle machine wash, but i just prefer using another normal cover on top of this, which i can wash frequently. It is not waterproof though so you need to be bit careful with liquids.