This is a brass bar of the nominal size indicated. It does not come polished, but with a bit of fine sanding and buffing it polishes very nicely. It's half-hard meaning its fairly stiff for its thickness. It cuts, drills, and taps nicely - obviously easier than mild steel, but harder than aluminum. When drilling and tapping I suggest using a light machine oil or WD-40 to save the wear on your bit and make the job go better.