WildGrow 4-port Lithium Battery Charger 3.7V 500mAH for Syma X1/X4/X5C/X5SC/X5A/X5/X5C-1, Udi, MJX, Freetech, Wltoys Quadcopter Drones FAST EFFECTIVE: 4 ports enable the battery chargers to charge 4 batteries at one time without interfering. SAFETY TECHNICIALShort circuit Protection with Over-Charge Protection (no need to babysit it) SMART INDICATOR LIGHTS: Each charging position has an indicator light that can tells you individually when the battery is fully charged (light off)or being charged (light on). CURRENT SPEC: DC 5V 0.52.5A current input, DC 5V 0.52.5A current output. APPLICATION:compatible with Syma X1/X4/X5C/X5SW/X5SC/X5A/X5/X5C-1; Udi U815/U816A/U818A; MJX T04/T05/F28/F29; Freetech H07N; Wltoys V929/V049/V059, etc.