1. Unique Design: This holder is designed with vacuum technology to suck hard and easy to slip floors, and it will stay in perfect condition even when not used on the floor. But it will not work on rugs on carpeted floors. It will not work on rubber backed rugs, jute rugs, or fluffy backed rugs. 2. Design Features. This product can be easily stuck under the carpet. There are small suction holes on the side facing the floor. These holes utilize the properties of vacuum technology, when pressure is applied from the top, air escapes from the low pressure area inside the suction cup. This creates a sticky effect that keeps the carpet in place. 3. Carpet anti-curl holder, 1/10 inch thick after installation, is inefficient. The suction technology adheres firmly to the ground without leaving marks or damage, and the grip easily separates from the ground. It is suitable for washing because you don't have to separate it from the carpet. For carpets, the tape adds extra comfort due to the slightly fluffy nature of the suction technology. This package contains 4 pieces. The grip measures 3.9 inches x 3.9 inches. Each piece is square to increase the surface area in contact with the floor. This can make your kitchen, bathroom and hallway feel more spacious. You can even use them outdoors to prevent shifting and straighten corners.