Each knife in the Zwilling J.A. Henckels Four-Star 2-Piece Rock & Chop Knife Set is forged with the Sigmaforge process from a single piece of high-carbon, German stainless steel, and Friodur ice-hardened to take on a razor edge with a 57 Rockwell hardness rating. An ergonomic polypropylene handle is permanently bonded to a 3/4 tang. The full stainless steel bolster provides balance, and features a pronounced finger guard. The Four-Star Rock & Chop Knife Set includes: 5.5" prep knife, and a 7" rocking Santoku knife. Manufacturer model #: 35177-002. Sigmaforge, single-piece construction High-carbon, stainless steel blades Friodur ice hardened steel Full stainless steel bolster Polypropylene handle Set includes: 4" prep knife 7" rocking Santoku knife