WIDENED TIRE DESIGN: our wheels are much wider than other ordinary wheels. The thickness of every tire is 1.8cm. The widened design can better protect the floor and the load-bearing capacity is also increased to 200kgas set of 5 HIGHT QUALITY : The entire support frame structure is integrally formed, with steel bearing, can providing many years effortless rolling and durability. High-quality soft TPR rubber material tires can protect your floors. FIT OFFICE CHAIRS : with standard size 11mm rod diameter, will fit 99% of standard stem five wheel office chair (Doesn't fit IKEA office chairs), making the work easier and more convenient for the user. EASY TO INSTALL: A simple 2 step assembly process, just take your old casters out and push your new ones in, and you are done.