The third generation QuickerTek Most Powerful eyeBattery (US$499.95) is 20% smaller and lighter than its predecessor. It comes in a rugged aluminum case styled to blend with Apple equipment.

The easy-carry model now features a USB port for quickly charging iPods, iPhones, iPads, and most USB mobile devices. What's more, the QuickerTek Most Powerful eyeBattery (http://www.quickertek.com/batteries.html) can provide up to 12 hours of extra computing time to a 15-inch Retina MacBook Pro running the battery friendly Mac OS X 10.9x Mavericks. It can provide up to 23 hours of extra battery life to a 13-inch MacBook Air.

QuickerTek’s Most Powerful eyeBattery is for any Mac laptop with a MagSafe 1 or 2 port, and every battery is shipped with the correct and properly-modified OEM [original equipment manufacturer] Apple MagSafe power cable, for plug and play. No drivers, no extra cables, and no adapters are needed. It also eliminate the need to carry an Apple recharger.

The latest Most Powerful eyeBattery also charges the internal MacBook battery while it powers the laptop. The recharge time for the Most Powerful eyeBattery from being totally depleted to fully charged is about four hours. The anodized, machined aluminum case features a 10-LED power gauge to show percentage-available charge levels of the external battery.

For electricity-free recharging you can connect a popular and rugged QuickerTek Solar Juicz fold-out solar panel. The 27 Watt model recharges a MacBook Air in 8 to 12 hours, weighs 1.78 pounds, and costs $700. The 62 Watt model recharges a MacBook Air in as little as six hours, weighs 3.15 pounds, and costs $999.