I'm using this pillow protector on a regular sized pillow, and it fits fine.  The inside is a light rubbery material to keep the allergens out, the outside is a nice soft quilted material that is very comfy.  There is a zipper closure also.  I do have a lot of allergies, so this is a big help to me.  Your pillow case will fit over it.  This would also keep bedbugs out of your pillow if you take your own pillow to motels.  Just in case!