Furniture Stopper: Our furniture cups feature a square groove design that fits wheels more securely, helps prevent sliding, and enhances stability; compatible with most furniture wheel types. Protect Your Floors: The caster cups are made of durable plastic material, resistant to scratches, noise, and wear; ideal for protecting floors from damage caused by daily furniture movement. Unique Non-Slip Design: Utilizes electrostatic adsorption technology at the base, providing reliable anti-slip performance on wooden floors and smooth surfaces. Wide Application: Suitable for use with chairs, shelves, pianos, sofas, bed frames, recliners, and other furniture in home or office settings. One Second Installation: Easy to install without tools—simply place furniture wheels into the caster cups; helps keep wheels from moving unintentionally. Size: 74x59x17mm / 2.91x2.32x0.67 inch Package Includes: 4 Pieces or 8 Pieces Furniture Caster Cups Note: 1. Please allow slight variation due to manual measurement. 2. Due to differences in monitor displays, the actual color may vary from the image.