Anker Astro Portable Batteries Comparison Read full Review. Charging Ports Best for: mAh name Group 1 Charging 1 Smartphone at full speed 6,000 Astro 1 2nd Gen Astro 2 Charging 1 smartphone at full speed + 1 standard USB device at full speed 9,000 Astro 2 2nd Gen Astro 3 Charging 2 smartphones at full speed + 1 standard USB device at full speed 12,000 Astro 3 2nd Gen Astro 2 Charging 1 small battery capacity tablet at full speed + 1 standard USB device at standard speed 10,000 Astro E3 Astro E 2 Charging 1 tablet at full speed + 1 standard USB device at standard speed 13,000 Astro E4 Astro E 2 Charging 1 tablet at full speed + 1 standard USB device at standard speed 15,000 Astro E5 Astro E 1 Charging 1 smartphone at a low speed 4,500 Astro Slim 2 Astro Slim 1 Charging 1 smartphone at a low speed 6,000 Astro Slim 3 Astro Slim 1 Charging 1 smartphone at a low speed 3,000 Astro Mini Astro Mini 2 Charging 1 large battery capacity tablet at normal speed + 1 smartphones at low-normal speed. 15,000 Astro Pro 2nd Gen Astro Pro 3 Charging 1 large battery capacity tablet at normal speed + 2 smartphones at low-normal speed. 20,000 Astro Pro 2 2nd Gen Astro Pro Read full Review. like and share this post: Share this:FacebookGoogleTwitterEmailPrintMoreDiggLinkedInStumbleUponTumblrRedditPinterest