EXCELLENT CLEANING - Waveform design dense bristles cover hard-to-reach areas for enhanced sonic cleaning for deeper cleaning. Compared to manual toothbrushes, it is easier to remove stubborn tooth stains and effectively improve the overall health of the gums. HIGH QUALITY BRISTLES - Cusnikelo brush heads are made of end-rounded Dupont bristles, advanced bristles effectively remove stubborn tooth stains from the surface of teeth while providing comprehensive care for teeth and gums, bringing a comfortable brushing experience. REMINDER BRISTLES - Blue reminder bristles on the toothbrush head help you ensure the most effective cleaning possible. Dentists recommend replacing toothbrush heads every three months. If the blue reminder bristles fade to white, you need to replace the brush head with a new one.