Sunyou Portable Multi-function USB Charger Dock For Samsung Galaxy S4 Mini (Black) This is an USB 3.0 Dual Cradle Charger with the battery Charge Slot, it is a fashionable and practicable design, with multi-function, it can finish the processes of Data HotSync and battery charging on your desk with a cradle. Perfect Designed for Samsung Galaxy S4 mini 2-In-1 Features: Synchronize--Charge Phone and Charge Extra Battery. Charge extra/ spare battery LED indicator