Shark 1/2 blades are for use in their straight edge barber razors that require 'half a blade'. Shark stainless steel blades are internationally known for being long lasting, exceptionally smooth and very sharp. If you use a straight edge razor that accepts half a double edge blade, this professional product is for you. There is no finer blade manufactured for straight edge razors/shavers. We have found that these blades deliver a particularly smooth shave. We know you'll think so too!