USBbuddy, Portable Powerpole (12V) to USB (5V) Converter and Device Charger | Powerwerx
Udoli 36W Universal Multi Port USB Car Charger 5 Port DC Adapter 5V 2.4A for iPad iPod iPhone Tablet Mobile Phone digital camera|usb battery pack charger|usb flash disk pricecharger set - AliExpress
Dual 12-Volt USB Charging Block 23638 - The Home Depot