Gillette MACH3 manual razors for men features stronger-than-steel blades that stay sharper longer (vs. Sensor3). With sharper blades (first 2 blades vs. Sensor3), it is engineered to last 15 comfortable shaves. These Gillette Cartridge 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 manual men's razor fits all MACH3 blade refills. For an incredible shave, use with MACH3 Turbo refills and MACH3 Extra Comfort Shave Gel. Frequent Ask Question (FAQ) What are Microfins, and what do they do? Microfins precede the blades and smooth out the skin before the first blade cuts the first hair. So you get a close, comfortable shave.