【Anti-slip Rubber】The chair caster cups are made of thick rubber, which has good traction, strong, sturdy, wear-resistant and long service life. It is black in color, very stain-resistant and easy to clean under running water. Package Included: Furniture Protector: 56 x 82 mm/2.2 x 3.23 inches, Thickness: 17 mm, 5 pieces. 【Protect Floor Surface】The anti-slip furniture caster pads protect floors from sliding furniture and prevent them from being scratched. The excellent rubber material can disperse the pressure of the furniture wheels on the floor and prevent invisible damage from the furniture to the floor. It does not require any installation, you just need to place it under the furniture wheels. 【Inner Curved Design】This is a non-slip pad for office chairs, which can effectively prevent the chair from moving on the floor when you don't need it. The inside of the non-slip pad adopts a curved design, which can fit the furniture wheels well, prevent the furniture from moving, and