The Oral-B Charcoal replacement toothbrush head features end-rounded, charcoal-infused bristles. Cup-shaped bristles remove stains, such as tea and coffee, for whiter teeth. The round brush head is inspired by dental professional tools for a tooth-by-tooth clean, with specially engineered bristles for optimal tooth coverage and better plaque removal in hard-to-reach areas. Each order comes with 8 Oral-B Charcoal Electric Replacement Toothbrush Heads. Fits most Oral-B rechargeable handles (Does not fit Oral-B iO). Dentists recommend replacing your brush head every 3 months for an optimal clean.