Our replacement toothbrush heads are made with filament, which has been recognized as the in the oral care synthetic filament industry for over 70 years. The bristles are made of American Thynex nylon. These rounded toothbrush heads are the trusted choice for gentle, - and effective brushing, plus oral . Innovative round head design, cup-shaped 360-degree full coverage of teeth, small and soft design, deep cleaning and care for gums High-density bristles adopt irregular hole hair-planting technology, the amount of hair is increased by 40%, and the cleaning of stubborn stains is more efficient You need to replace the toothbrush head. Generally, we recommend that you replace it at least every 3 months. Color: Black Material: Plastic+bristles Package Contents: 9 x electric toothbrush head Only the above package content, other products are not included. Note: Light reflection and different displays may cause the color of the item in the picture a little different from the real thing. The measurement allowed error is +/- 1-3cm.