The Oral-B EB50 CrossAction replacement brush heads come in a pack of four black heads designed for adult users. These round heads feature medium bristles set at a 16-degree angle, which allows them to reach deep between teeth to remove up to 100% more plaque than a manual toothbrush. Constructed from plastic and rubber, these attachments are compatible with the entire range of Oral-B handles, with the exception of the Pulsonic model. To maintain effective cleaning performance, you should replace the head every three months.