Made with Japanese 440C Cobalt Stainless Steel these newMaster Grooming Tools 5900 Series Japanese StainlessSteel Thinning Shears have a Rockwell Hardness Ratingof 59 and are ultra-sharp for excellent performance. 30-Tooth Thinning Shears are ideal for bulk thinning on very thick coats going underneath the surface and against the grain; 46-Tooth Thinning Shears are great for shaping and blending Micro-serrated edges hold hair in place while scissoringshort shanks reduce hand fatigue removable finger rests for comfort The dialed tension knob makes it easy to set the cutting tension Material: 440C Japanese Cobalt StainlessSteel. Size: 30-Tooth 6 1/2" Shears and 46-Tooth 61/2" Shears Rockwell Hardness Rating: 59