Description: S-series. 4wd. Disc brake. Cross drilled for quick brake response and heat dissipation Black coating on hat and vanes Quality validated for proper metallurgy and correct brake plate thickness Tighter tolerances similar to GM OE specifications Some ACDelco Gold parts may have formerly appeared as ACDelco Professional Premium aftermarket replacement part Manufactured to meet specifications for fit, form, and function for General Motors vehicles as well as most makes and models