TOMO V8-4 Intelligent 18650 Portable Power Bank & Battery Charger 2 in 1 with Double Output and LCD display (Black) DIY YOUR POWER BANK. TOMO is not only a power bank, but also a charger for 18650 batteries. You can use 1-4 batteries or charge 1-4 batteries at will. SMART USB PORT. The double USB ports of 1A/2A can charge the cellphone and the tablet PC at the same time. The intelligent identifying function will provide the most suitable current output for the cellphone and the tablet PC, which not only increases the charging efficiency, but also provides care to the components inside your digital devices and protects them from being damaged. MULTIFUNCTIONAL LCD DISPLAY. The power quantity of the 4 batteries is shown separately with the simple 5-bar display, which helps you keep track of the current condition of power and travel at ease; While charging for other devices, the LCD display screen will show you the status of the current and the voltage at the moment. BATTERY PROTECTION FUNCTION. If the positive and negative electrode of a certain battery is placed reversely, the corresponding LCD display screen of the battery will be empty, but the usage of other batteries will not be influenced. You can also use this function to check if the battery is damaged. When you insert a healthy battery, the TOMO device will turn on automatically. GOOD COMPATIBILITY. This product is compatible with all sorts of devices and digital products, including over 95% of the brand mobile phones, tablet PCs, iPods, PSPs, MP3s, MP4s and bluetooth devices on the market.