Copper plating is commonly used as a heat treat mask and is also known for its high electrical conductivity. Offering excellent throwing power, copper gives a smooth uniform finish. Conversely, we can strip copper off post heat treat as well. Our experience with copper plating is mostly as a heat treat mask for aircraft parts, and we've been doing it a very long time! Shafts, bearings, flanges, etc. Again, we can offer excellent turnaround time pending wire, rack or barrel, quantity, size, and cleanliness. Copper finishing tip.....steel wool shines it up just like a brand new penny!