Satin finish. The 85mm throttle body for 1998-2002 LS1/LS6 Camaro and Firebird is typically suitable for use on Professional Products 52060/52061 LS1 Typhoon intake manifolds as well as other LS1 aftermarket intakes. This throttle body features die cast aluminum construction and are O.E. quality units. Utilizes an aluminum transition plate that bolts between the stock manifold and the throttle body. This transition plate smooth the flow of air when using the throttle body on a manifold that has an inlet opening smaller than the throttle body. These units are a direct bolt-in replacement for the stock throttle body. Our throttle body also fits 2004 Pontiac GTO and full size 4.8, 5.3 & 6.0 engines with cable style throttle linkage.