Amazon travel backpack is United Airlines-friendly and ‘holds surprising amount’

The ECOHUB Travel Backpack, which measures 17x10x9 — the exact dimensions allowed by United Airlines — typically goes for $40.99. But with a coupon offering 10% off, the bag is on sale for $36.89. The bag comes in six different colors, ranging from black and green to red and blue. It boasts a capacity of…