Bed bugs cannot jump or fly and move around only by crawling. Our Bed Bug Blockers are designed with this in mind, using a textured exterior surface to allow bed bugs to easily climb in and a slippery interior reservoir to prevent bed bugs from climbing out. Bed bugs are attracted by the carbon dioxide that humans and animals emit as they sleep at night. Ensure your Bed Bug Blockers are the only path bed bugs can travel through in order to attempt to reach your mattress.