The overall dimension of the wheel (diameter x width) is 150mm x 24mm (5.9" x 0.94"), the inner diameter of the center bearing is 8mm (0.31"), and the length of the axle screws is 75mm (2.95"). Please check the detailed dimensions in the product images before purchasing. Package includes 2 gray front spare wheels and 2 axle screws. Easy and convenient to install without complicated steps, saving time and effort. Made of high-quality, environmentally friendly solid rubber, this replacement wheel set is anti-slip, dustproof, highly wear-resistant, and load-bearing. Suitable for a wide range of mobility devices including wheelchairs, walkers, rollators, and other similar equipment with 6-inch wheels. Provides a quiet, smooth, and lightweight ride on all surfaces—ideal for both indoor and outdoor use. Economical, practical, and built for long-term durability. Specifications: Material: Solid Rubber Color: Gray Overall Wheel Dimension (Diameter x Width): 150mm x 24mm (5.9" x 0.94") Center Bearing Inner Diameter: 8mm (0.31") Distance Between Bearings (on both sides): 40mm (1.57") Axle Bolt Length: 75mm (2.95") Total Weight: 700g Package Includes: 2 x 6-inch gray front spare wheels 2 x axle screws