Oral-B Replacement Brush Heads, Set of 4 I bought a large quantity at Costco, but I have some left over since I didn't use all of them, so I'm selling them. They are unopened, but they have been handled by a person once, so please refrain from purchasing if you are sensitive to this. Oral-B, the brand recommended by dentists worldwide* Advanced Multi-Action Brush The X-shaped bristles scrape away plaque from areas that regular bristles can't reach, for a deeper clean. The green bristles fade to white to indicate when it's time to replace the brush head. Maintains the best plaque removal performance.