This set of 4 wheelchair drive parts includes 4 black front replacement wheels, each equipped with 2 bearings, for a total of 8 bearings in the set, meeting daily replacement and spare needs. The wheel diameter is approximately 7.5 inches, the inner diameter of the center bearing is about 0.3 inches, and the wheel width is 1 inch. Please check the dimensions before installation to ensure proper fit. The wheelchair replacement wheels are made of high-quality rubber with a stable and durable structure, suitable for both indoor and outdoor use. The rubber features high hardness with good load-bearing and wear-resistant properties. The replacement wheels are easy to install and remove, and with high-quality bearings, they are lightweight and portable, providing quiet, smooth and effortless rolling on various surfaces, offering stable support for mobility. These replacement wheels have wide compatibility and can be used on disability vehicles, medical equipment, and most wheelchairs, walkers and other devices fitted with 7.5-inch wheels.