FULL COMPATIBILITY: Compatible with FW507/508/515/551/917/959/D7/D8/D3/D1/2011; Compatible with SG E9/507/515/575/909/917/949/958/908/610/659/719/910; Compatible with HP126A/HP150A; Compatible with Dnsly TB5; Compatible with Fairywill/Sboly /ATMOKO /Teeteck.(NOTE: Does NOT fit Fairywill E11/ 2001/ 2081/2205/2209/921) DUPONT QUALITY BRISTLES: The bristles are made of DUPONT nylon, a professional, high-quality bristle material for toothbrush heads. The bristles are just right between soft and hard, ideal for cleaning around sensitive areas and fighting food particles and plaque! EFFECTIVE AND CLEAN: W-shaped bristles designed to fit well with the topography of the teeth to ensure that the toothbrush heads reach all areas for thorough cleaning of the gums and easily remove hidden plaque! Reminder bristles fade to let you know when it's time for a replacement. ROUND BRISTLE TOP: The bristle tops are rounded through a polishing process for safety and gentleness. So your gums are protected. The replacement heads are extra gentle and comfortable for teeth and gums than standard replacement brush heads. High reliability for bristle planting to ensure that the bristles do not fall out. VALUE PURCHASE: 10x replacement brush heads with vacuum packaging at an unbeatable price. Dentists suggest replacing your toothbrush head at least every 3 months. Our replacement brushes last for months or even years. It fits as a gift for your family and friends.