100-ct "Derby Professional" Single Edge Razor Blades for straight razor. Cutting-edge spluttering equipment coat the edges of each blade in chromium-ceramic tungsten and platinum for a truly unmatched shave every time. Double edged blades are increasingly only used to be split in half. These single edged razors are made specifically for such shaving utensils and each are individually wrapped in wax paper to maintain excellence and sharpness. Chromium-Ceramic-Platium-Tungsten and Polymer Coated Edges Derby Single Edge Razor Blades are designed to be incredibly durable and long-lasting, made from the highest quality steel strip in their hallowed Swedish factory.