The Oral-B CrossAction brush head with bacteria protection bristles is our most advanced brush head and prevents bacterial growth on the bristles. It cleans 100% better than a regular manual toothbrush, while the bacteria protection bristles help keep your brush head clean. The perfectly angled bristles reach deep between teeth to remove plaque. The blue indicator bristles indicate when to change the brush head. The brush head is compatible with all Oral-B electric toothbrushes except Oral-B Pulsonic. 4 Oral-B CrossAction replacement toothbrush heads with bacteria protection are included.