Authentic. Up to 15% saving per refill (First two blades vs. Sensor 3 Disposable). Lubrication Strip (First two blades vs. Sensor 3 Disposable). Microfin skin guard. All Mach3 cartridges fit all Mach3 Handles. Gillette the best a man can get. P&G. www.pg.com. Anti-theft. US: (First two blades vs. Sensor 3 Disposable) Compared to per-cartridge cost of 4-ct pack, based on manufacturer's cost to retailer. Pricing is at the sole discretion of the retailer. CA: (First two blades vs. Sensor 3 Disposable) Compared to per-cartridge cost of 5-ct pack, based on manufacturer's cost to retailer. Pricing is at the sole discretion of the retailer. www.Gillette.com. www.pg.com. Comments? 1-800-GILLETTE. www.Gillette.com.