Yes, the castors are for hard floors. The inner part is made of black hard plastic, the outer part of the castor is made of grey hard rubber. Since the castors are braked (is now a regulation), the hard rubber covering seems more suitable for carpets at the beginning. When the castors are new, they do not turn optimally (vertically). After a short time of use, however, this will disappear. I also use the office chair on a hard floor (vinyl) and am very satisfied with it. It is light, comfortable and manoeuvrable. By the way, I had the same uncertainty about the castors and therefore asked Giroflex. It's not readily apparent to outsiders and should be specified more clearly in the product description. Otherwise: Have fun, it's a really good product.