Description: These spreader bars distributes clamping pressure evenly to create better seal between valve cover and cylinder head. Made of durable material, corrosion resistant with long service life. This is a non-OEM product, accessory only! Specification: Color: Silver Tone Material: Aluminum Alloy Hole Diameter: 8mm / 0.31'' Dimension: 121.5x18x5mm / 4.78''x0.71''x0.2''(L*W*H) Fitment:for Chevy 283 305 327 350 383 400 engines with small blockPackage Included:8 x Valve Cover Spreader Bar