Small power banks are a dime a dozen, but Iniu's Pocket Rocket P50 stands out for its combination of size, capacity, and features. We saw this model drop in price during Amazon's recent October Prime Day sale, but a fresh discount has now made the power bank cheaper than ever. Right now, you can pick it up at Amazon in black for just $13.74 (a little over $19 off) after applying the automatic 45 percent off coupon at checkout.