Feather Japan F11 Neo Twin Blade Cartridge Replacement Pack includes 10 cartridges that are very sharp and don't tug and tear like some other blades do. These blades give a close shave, less passes and almost no irritation. Each twin blade cartridge has 2 Platinum and PTFE coated blades that combine to give a close, comfortable shave. These cartridges are designed for smooth swivel and has a cutting angle for matching the contours of your face. These cartridges are designed for two-blade razor better than other multi-blade cartridges with three and more blades, the less metal on the face the less irritation you'll get.