100% Money Back Guarantee- We truly want you to be happy with your new replacement heads and our professional customer service will do whatever it takes to ensure your satisfaction we are offering a 6-month guarantee, no questions asked. Well-designed end-rounded bristle to be safe and gentle on teeth and gums, it is what you care about most.5 replacement brush heads for long term usage. American Dental Association recommend to replace brush heads every 3 months to avoid exceeding breed of bacteria. Unique W shape brush head design and innovative 3D cutting process allows each tooth to be cleaned in three dimensions. The bristles are waved to match the shape of the teeth to thoroughly clean gums and hard-to-reach areas. Feel the difference of US DuPont bristles! Long-lasting quality, medium hardness, gently removes 100% more stain and plaque than ordinary toothbrushes to improve gum health. Our toothbrush heads compatible with FW-D1 / D3 / D7 / D8 / FW507 / FW508 / FW515 / FW551 / FW917 / FW959; Compatible with SG-E9 / SG-507/SG-508 / SG-958; Compatible with TB-5, Compatible with HP126A/HP150A;. ( DOES NOT Fit FW-E11;P11;P80; 2001; 2081; 2205; 2209; 921 ).