[DURABLE CONSTRUCTION] Made of metal, designed for efficient heat dissipation and flexible rotation to enhance durability. [PROVIDE SMOOTH MOTION] Includes spacer, axle, and extra side plug for improved bearing support, helping reduce friction and ensure smoother bearing operation, while helping prevent bearing damage. [EASY TO MATCH] Recessed spacer design fits securely between bearings for seamless wheel integration, providing stable support for wheels and bearings; compatible with standard male and female skating axles. [COMPATIBILITY & SIZE] Axle diameter: 6mm, frame spacer inner diameter: 6mm, wheel spacer inner diameter: 8mm. Suitable for most roller skate models using 6mm axles. Please verify dimensions in the product images to ensure compatibility. Accurate measurement of your wheel bearing is essential for proper fit. Style: A Color: Silver Material: Metal Package Contents: 10 x Axle, 2 x Wrenches, 16 x Side Plugs, 8 x Three-Section Aluminum Casings, 10 x Screws Package includes only the items listed above; other accessories not included. Note: Lighting and display settings may cause slight color variations between the image and the actual product. Measurement tolerance: +/- 1-3 cm.