When you feel your shave isn't as smooth or as close as normal, it's time to reach for the King of Shaves Azor Hybrid Synergy System Endurium Razor Blades. Working in tandem with the award winning Azor razor, these four blades define shaving simplicity. To remove your old King of Shaves Azor Hybrid Synergy System Endurium Razor Blade, hold the razor handle and use your thumb to 'ping' off the cartridge by pressing firmly down on the little Azor logo (on the razor's head). It doesn't take much practice, and it's easily done. Alternatively, you can slide the used cartridge back into the tray and remove by pulling the handle upwards whilst gently pressing the Azor logo down with your thumb.