The Colt Cobras and Agents have lightweight frames that are anodized, an external hardening finish. Once that finish is worn away you probably could gouge it with a knife. I've seen some Cobras with so much finish overall gone they do look like dull stainless. They make fine carry guns affording an extra 6th shot over most competitors 5. The Cobras and Agents and K,J frame Smiths tend to crack the frame at the 6 oclock barrel point if you shoot them with heavy loads. Something to look for if you contemplate buying one. Supposedly the post '66 short butt D frame Colts like the Cobra are safer to shoot heavy loads. The only one I've got left is a '69 DS. Colt won't refinish alloy guns anymore and parts are tough to find. If your Cobra locks up properly don't use it as a regular range gun, just load it up and stick it in your pocket.