As one of its daily deals, Woot offers the Gorilla Gadgets Uhuru! 16,800mAh External Battery Pack in Black or White, model no. CHR-150, for $39.99 plus $5 for shipping. That's the lowest total price we could find by $25. It features 2A / 1A dual output and an LED screen, and includes an Apple lightning-to-micro-USB adapter, Apple 30-pin adapter, and micro-USB connector. Deal ends today.