The MERKUR SUPER blade is a classic double-edge blade made of stainless steel with a platinum coating. There is no fixed period for the durability, as the firmness and density of the whiskers can differ too much. The classic blades in connection with a safety razor are usually more economical cost-wise than system blades. Just like a straight razor blade, the double-edge blade’s cutting edge is very fine and elastic. That is why it must never be wiped off, and should be used for a shave no more than once a day. The ridge needs to straighten up, otherwise it will break off and the blade will become dull quickly. If the shave causes tiny injuries, it is an indicator that the blade is worn out and must be replaced.