Sunvalleytek via Amazon offers the RavPower 16,000mAh External Battery Pack in Black or White, model no. RP-PB19, for $39.99. Coupon code "PORE2QIZ" cuts the price to $30. With free shipping, that's $3 below our mention from last week, a current low by $6, and the best total price we've seen. It features 1-amp and 2.4-amp USB outputs and is compatible with iPhone, iPad, iPod, and many smartphones.