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.