These black swivel casters are made of durable plastic, perfect for chairs. - Color: Black - Type: Casters - Material: Plastic - Application: For chairs - Design: Swivel - Side-to-side diameter of the wheel is 4.5cm Thank you for viewing. Casters for office chairs [Set of 3] ■ Condition - Unused (stored item) - No noticeable scratches or stains ■ Specifications - Insert type casters - Smooth rotation, quiet type - Can be used for office chairs, desk chairs, DIY furniture, etc. ※ Most chairs use 5 casters. ※ This product is a [set of 3], so please use it for replacement or replenishment. Instant purchase is OK. Thank you.