COBALTIMA tweezers are made entirely from a patented alloy containing Cobalt for added strength and corrosion resistance to acids. The hardness of the tips is progressive and reaches its peak in the deployment zone where we have measured a Rockwell C hardness of 63/64 for model 5-CO, which makes it harder than Stainless Steel while remaining anti-magnetic. This alloy is resistant to temperatures up to 500 degrees Celsius (932 degrees Fahrenheit). It is highly recommended for autoclave sterilization. In addition all COBALTIMA tweezers have radiused inside edges and outside finger serrations for positive gripping.