Oral B Compatible Replacement Toothbrush Heads Electric Toothbrush Rechargeable Heads SB-17A Replacement Tooth Brush Heads for Oral B. Soft bristles with rounded ends for comfort. Clean teeth and massage gums gently while effectively removing plague without irritating gums. Dentists recommend you replace the head every three months. These replacement heads have color bands so each family member can have their ownthe bristles will also change color to let you know when its time to change heads. Available in 4, 8, 12, 16, 24, and 32 packs.