The pro series 5-Inch c clamp features heavy duty frame with a smooth baked enamel finish that resists rust and corrosion. The drop forged steel screw is precision machined for smooth operation. Copper coated spindle resists wear, corrosion and welding spatter.The drop forged steel screw is precision machined for smooth operationCopper coated spindle resists wear, corrosion and welding spatterSmooth baked enamel finish resists rust and corrosionLifetime warranty