Works best with these Braun Series 7 Shavers: 7120s, 7125s, 7127cs, 7171cc, 7175cc, 7185cc and 7189cc; it is compatible with all Braun Series 5, 6, and 7 flex new generation shavers Replace the head after 18 months to get a shave as efficient as day one with your existing cordless shaver Easily click the new foil shaver head into place Wet and dry shaving functionality ensures that you can use the trimmer with or without water Features waterproof floating and pivoting heads with three blades, ensuring even results each time you use it AutoSense technology with 360-degree flex head ensures a smooth, close shave