High quality: The double wheel design allows for higher loads on the casters compared to a single wheel. The furniture wheel tread is made of high quality rubber and will not scratch your floor at all. The construction is solid, the material is tough and durable, and the support is good. Installation: The wheels are screwed in using a screw plate, screws are included and others screws can be used if necessary. Applications: Ideal for use with your indoor and outdoor furniture on universal floors such as carpet, PVC, vinyl, tiles, concrete smooth and stone floors. Total load: The casters can support up to 40 kg per wheel, and the 4-piece set can support a total load of 160 kg, making them suitable for flexible movement of a wide range of furniture. Easy handling: the ball bearing is securely enclosed in a robust housing in a swivel plate, which makes changes of direction particularly easy and allows for more dexterous handling .