Built for speed and simplicity, Hydrogen SK-9 Bearings feature an integrated spacer system, so there's no need to install separate spacers. This specific design keeps bearings properly aligned when tightened and makes installation quicker and easier. Seven chrome steel balls, a durable steel body, nylon cage, high-temperature grease, and dual rubber shields deliver reliable performance and easy maintenance. Each pack includes 16 bearings for a streamlined setup.