Xiaomi T700 Electric Toothbrush Replacement Heads Black are specially designed for sensitive teeth, has soft and non-irritant bristles that go extensively into the gap of gums to clean teeth stains. They have smaller 4mm ultra-thin brush head so reduces discomfort, and helps to easily clean the oral corners. The higher density and convex-shaped bristles will bring more thorough cleaning experience. With the bass brushing method, the 45° inclined vibration around and under the gumline will helps to comprehensively remove food residue and soft dirt.