GRAPHITE COATED BLADES: Engineered with graphite coating, the foils offer longer lasting performance, and a consistently close shave every time. ADVANCED 3-STAGE CUTTING SYSTEM: This shaver replacement head pairs with the F4 & F5 innovative cutting systems that delivers precise results, whether you’re trimming longer hair or tidying up stubble. SHAVE WET OR DRY: The Remington F4 Shaver head is waterproof and easy to use in or out of the shower with your razor. F4 & F5 COMPATIBILITY: Designed to work seamlessly with F4010 and F5010 foil shaver models. MAINTAIN PEAK PERFORMANCE: Keep your shaver operating like new! For the best shave, replace the heads and cutters every 6 months—Remington makes this easy!