Our zippered premium mattress encasement completely encloses the mattress, acting like a protective layer over the top, bottom, and sides of the mattress. It is designed this way to trap and act as a barrier against bed bugs inside mattress cutting their primary survival source that is blood. Once the mattress is encased, other bed bugs hiding in bed rails, carpets, luggage or other items may not be able to enter the mattress. These tiny, brownish pests are more visible and easier to catch outside the encasement than if they are on a bed sheet. Our escape proof mattress encasement features a zip guard to ensure the zipper is tightly and completely sealed.