These high-quality special casters are designed specifically for use on hard floors like parquet, laminate, tile, or stone, featuring a durable polyurethane surface coating. Each heavy-duty caster has a maximum weight rating of 100 lbs, with a total capacity of 500 lbs when used as a set of five. The pressure-activated safety feature ensures that the chair rolls smoothly while seated, and the casters automatically brake when standing to prevent any unintended movement. Installation is quick and easy, making these casters a perfect upgrade for your office chair.