Bought the Anker Astro E4 13000mAh External Battery from Amazon at a promotion price of US$36.99 (S$46) excluding shipping. The usual price is US$43.99 (S$54.56).
The Anker Astro E4 is my third Anker Product and I must say, I am really love this up and coming brand. It seems very popular in the US. The Anker Astro E4 tops the Gizmodo’s Five Best External Battery Packs.