Philips Norelco Genuine SH91/52 Replacement Shaving Heads Compatible with Norelco Shaver Series S9000 and 9000 Prestige, Latest Version for Refreshed SH90/70, SH98/70, and SH98/80In two years, your Philips shaver heads cut up to 9 million hairs on your face replace the shaver heads and get your electric razor back to 100% performance. Ultimate durability with self sharpening blades made of similar steel as in the aerospace industry, designed to stay sharp and resist even the toughest conditions. Advanced precision for a closer shave* with 72 high performance self sharpening Dual SteelPrecision blades made of Swedish steel for