Amazon is currently selling the higher-capacity version of the Anker Astro E7 power bank at a heavily discounted price.

According to the retailer's website, the newer Astro E7 can hold up to 26,800 mAh battery juice, enough to fully charge the iPhone 6 up to 10 times. The iPhone 6s and Samsung Galaxy S6 can be maxed out six times while the larger dry cell inside the iPad Air can be brought back to 100 percent twice.

The newer Astro E7 can now be obtained for $60. That's a 50 percent discount from its list price of $120 and a $140 savings from its original launch price of $200. For only $60, customers will be getting a power bank that charges devices at speeds as fast as three amps.

The device is fitted with premium cells and top-tier circuitry for reliable and safe charging. Externally, it sports a durable glossy build complete with a LED flashlight, which can be enabled by double clicking on the power meter button.

The package also includes a travel pouch, welcome guide, 18-month warranty and customer service from Amazon.

The offer is one of the best power bank deals out in the market today. Not all smartphones are well endowed in terms of battery capacity, which makes the 26,800 mAh Astro E7 the most important mobile accessory $60 can buy. Also, it makes for a great holiday gift.

In other Amazon news, the popular online retailer has just revealed its latest prototype of the Prime Air drones, which the company hopes will soon be used to deliver packages in less than an hour.

USA Today points out that the unmanned device tips the weighing scale at 55 pounds and could lift objects weighing six pounds and under. It uses "sense and deploy" technology to avoid aerial obstacles while going to its delivery destination.

"We are testing many different vehicle designs and delivery mechanisms to discover how best to deliver packages in a variety of environments," reads a statement from Amazon Prime. "We have more than a dozen prototypes that we've developed in our research and development labs. The look and characteristics of the vehicles will evolve over time."

Earlier this year, the Federal Aviation Administration (FAA) approved Amazon's drone tests as part of its research on the Prime Air delivery service.

Other firms have also sought the FAA's approval for the use of drones as a more convenient and fast method of delivery. Google has announced it plans to launch a drone service in two years' time while Walmart is seeking permission from the FAA to begin drone testing.