Description: 1900mAh External Backup Battery Portable Charger Case For iPhone 4 4S Easy installation and removal. Ultra-thin design and perfect dimension. LED battery charge indicator lights and on/off button. Works as both an extended iPhone battery set and a protection case. Color: Black/ White 4 level Light indication for battery status. Intelligent IC effectively avoid short circuit. Specifications: Input Voltage: 5V Input Current: 500mA Output Voltage: 5V Output Current: 500mA Practical Capacity: 1900mAh Input Charging Time: 4 hours Operating Temperature: 0?-45? Temperature Range Transportation & Storage: -20?- +50? Battery Type: Lithium ion battery Charge Cycle Times: More than 500 times Product Size: L125*W63*16 mm Weight: 63g Package Included: 1x Battery Charger Case 1x Charge Cable Note: 1. Please connect the battery in parallel, in accordance with the circuit board. 2. If you reverse polarity wrongly, the board will get burned and we will not responsible for erroneous operation!