PS:Replacement for BAIR Kids K7 1. Soft DuPont bristles, well matched for sensitive teeth to use 2. Ultrasonic electrical toothbrush can effectively eliminate plaque and decrease gingival necrosis. 3. Adopt DuPont American tynex basic 0 bristles bristles,gently in your teeth. four bristle tip diameter, deep clean the space between teeth five accredited by way of FDA and UV sterilized. 6 sealed packing, way more secure to use. 7 replace the toothbrush heads every three months 8 you've got any questions on the toothbrush model, you could consult visitor service. Thank you.