e Tap batteries are literally a snap to remove & charge. Just flip the tool-free battery latch up & slide the battery up & out of the derailleur. Then snap the battery into the USB (Universal Serial Bus) powered charger & connect the charger to any USB (Universal Serial Bus) power source or A/C USB (Universal Serial Bus) adaptor. A full charge takes just 45 minutes to complete. Easy & fast charging for your SRAM RED e Tap batteries.