Sunvalley Brands via Amazon offers the RAVPower 10,000mAh High-Speed Battery Pack for $17.99. Coupon code "DEL10000" cuts it to $14.99. With free shipping for Prime members, that's tied with last month's mention at $65 off list and the lowest price we could find. It features dual USB 2.0 ports and 3.4-amp output. Deal ends December 31.