Kershaw Copper Natrix - Folding Knife - Model 7007CUKershaw Copper Natrix (Mid Size) The copper Natrix now comes in small, medium, and large. With its 3. 25 inch drop point blade, this medium sized Natrix makes a perfect EDC and offers solid performance. The blade is D2 blade steel, a high carbon tool steel thats highly wear resistant, tough, and offers excellent edge retention. The denser than steel copper handle gives the knife has some heftbut it still comes in under five ounces. Over time, the