• Measure the connection bolt of your old wheels to the millimeter: 11 mm bolt diameters fit many office chairs. • The wheels are inserted into the corresponding opening of your office chairs with the help of a connection pin. No tools are needed for assembly. • Ideal for hard floors such as laminate, vinyl, or tile. • A complete set is supplied, consisting of 5 wheels - each wheel can support a load of up to 35 kg, a total of 175 kg per set. • Ideal for your office chair in the study, home office, or game room. • Abrasion-resistant material prevents annoying tread marks on your floors.