Brush heads for thorough cleaningThis pack comes with 4 Medium brush heads. The front is provided with a symbol so you can distinguish which one is yours!- Bristles that fade in colour- Soft, rounded Dupont bristles- With a symbol on the front side to distinguish which is yours- Includes 4 Medium brush heads- Suitable for sensitive gums and teethSonicYou’s brush head includes fading bristles that change in colour the more you use it. They will let you know when the brush head needs to be replaced. The brush head is suitable for sensitive gums and teeth but still cleans the teeth thoroughly. Also available in “Soft”. Silk’n SonicYou Refills White Regular 4 st