Suction Underside Grips to Floors: adhesive topside adheres to carpet while nonadhesive suction foam underside grips to floor; similar to suction stickers, the grippers underside is composed of hundreds of tiny, open pores; when pressure is applied, air escapes creating a vacuum effect allowing gripper to firmly stick to the floor without leaving residue or causing damage Prevents Curling, Bunching and Sliding: designed with strong nano suction foam, hard floor grippers help to keep rugs in place and prevent curling, bunching and sliding Gripper is concealed and stays hidden under rugs; great for securing rugs in family rooms, bedrooms, offices and more Removable and Easy to Use: to install, simply peel and stick gripper to rug bottom; peel off other side, position your rug and press rug firmly to the floor; to remove gripper, lift rug until it detaches from floor; grippers can easily be lifted from floor while remaining attached to your rug so that your rug can be repositioned and reused in other areas of your home; grippers can be machine washed along with your rug and replaced on floor after being air dried thoroughly Use on Rug Corners or Sides: generously sized square design fits perfectly on rug corners or sides; 4 by 4 inch design maximizes surface area for a secure grip; grippers can be trimmed if needed; for use on most hard floors, laminate, tile, and cement