This set of 5 office chair rollerblade wheels caster is designed for heavy-duty use with a 3-inch diameter and made of durable polyurethane material in black and clear color. The caster wheels feature smooth and quiet rolling, making them ideal for office chairs, tables, and other material handling applications. With a 7/8 inch stem length and 7/16 inch stem diameter, these caster wheels offer a reliable and stable solution for your workspace needs. Made in China, these units come in a bundle listing and are perfect for enhancing the mobility and functionality of your office equipment.