Amazon.com: BORNMIO Replacement Battery for Oral-B Professional Care 8500 9900 Toothbrush 3731 3738 (2500mAh) : Health & Household
Replacement Battery for Braun Oral B 3745 3728 3762 7000 3731 P7000 D25 D28 Electric Toothbrush 1.2V 42mm x 17mm Batteries|Replacement Batteries| - AliExpress
Amazon.com: FDK OEM NiMH Replacement Battery Compatible with Braun Oral-b Triumph Professional Care Toothbrush with Narrow Tabs, (48L x 17D mm, 2700 mAh) : Everything Else
Amazon.com: FDK Replacement Battery Compatible with Braun Oral-b Triumph Professional Care (Type 3731 or 3745) Toothbrush (42mm Long, 17mm Diameter, 2150mAh) : Everything Else