The document summarizes wheels and tires. It discusses the requirements of automobile wheels, including being strong, balanced, lightweight, and easy to remove/mount. Standard wheels are steel, while some vehicles use aluminum or magnesium alloy wheels. Valve stems allow inflation/deflation and retain air. Wheel studs and nuts attach wheels to hubs using correct torque for safety. Common wheel types include steel, alloy, spoke, divided, and split rims. Custom wheels come in aluminum variants and differ in offset for handling characteristics.