Chrome vanadium, chrome plated, polished. With traction profile.
12k mm: 18.0 length: 66.0mm diameter: 24.4mm depth: 20.0mm PROFILE: BI-HEXAGONAL SIZE / SIZE: 18 MM DRIVE: 3/8 INCH LENGTH: 66.0MM FOR IMPACT GUNS: NO MAGNETIC: YES PIN TO RELEASE: NO INSULATED VDE: NO