Reignet via Amazon offers its Reignet Replacement Charger for Fitbit Flex 2 for $9.99. Coupon code "7LK9V38J" drops it to $5.99. Plus, Prime members bag free shipping. (Non-members can spend $49 or more to qualify for free shipping; otherwise, shipping costs $6.49.) That's $24 off and the lowest total price we could find. It features a reset button and 6.7" cable.