Compatible with All SNAP-ON Philips Sonicare Electric Toothbrush handles NOT Compatible with Essence, 5611/01 E-Series, HY1200NOT Compatible with Philips One SeriesCompatible with Philips Sonicare brush head system: snap-onCompatible with DiamondClean brush handles (ALL Models)9322 9331 9332 9334 9336 9340 9342 9350, 9351 9352 9361 9362 9371 9372 9381 9382Compatible with ExpertClean (ALL Models)Compatible with ProtectiveClean (ALL Models)Compatible with 4100 new 4100 4100+ (ALL Models)Compatible with FlexCare (+)/ FlexCare Platinum (ALL Models)6921 6930 6950 6972 6973 6992 9140 9141 9142 6970 6934 6902 6903 6910 6920 6932 6985 9110 9111 6911 6952Compatible with HealthyWhite (+) (ALL Models)8923 8911 8918 6710 6712 6722 6730 6732 6733 6750 6761 6781 6782 6780Compatible with EasyClean (ALL Models) 6201 6211 6212 6220 6231 6221 6250 6252 6253 6530 6510 6511 6512 6552Compatible with Sonicare for Kids (ALL Models) 6311 6320 6322 6330 6340Compatible with 2 Series plaque management (ALL Models)6220 6211 6231 6201 6212 6221 6250 6252 6253Compatible with 3 Series Gum Health (ALL Models)6631/01 6632/09 6616/50 6616/51 6616/52 6631/01Compatible with Essence+ (ALL Models)3211 3281 3211 3281