With sharper blades (first 2 blades vs. Sensor3), it is engineered to last for 15 comfortable shaves. These Gillette razors feature a lubrication strip that glides to help protect your skin from redness, and a microfin skin guard that stretches the skin, and prepares hair to be cut. Mach3 men's razor blade refills fit all Mach3 razors. This pack includes 4 Mach3 razor blades. Stronger-than-steel blades stay sharper longer (vs. Sensor3) Each razor blade refill is engineered to last for 15 comfortable shaves Features sharper blades (first 2 blades vs. Sensor3) Lubrication strip glides to help protect your skin from redness Advanced skin guard helps stretch your skin, and prepares your hair to be cut Fits with any Mach3 razor handles