Bluetooth Wireless Dongle USB receiver for Fitbit ONE / Flex / Zip / Charge / Force / Charge HR / Surge / Blaze / Alta Wristband - AliExpress
Fitbit Wireless Sync Dongle USB For Charge, HR, Flex, One, Zip, Alta, Surge OEM | eBay
Amazon.com: Fitbit FB150 Wireless Sync Dongle with USB Charging Cable Cord for Fitbit Flex Wireless Activity Tracker - Bulk Packaging : Electronics
Compatible for Fitbit Alta Charger, Replacement USB Charging Cable Cradle Dock for Fitbit Alta and Fitbit Ace Fitness Wristband (1-Pack 1FT/30CM)(Not for Alta HR) - Walmart.com