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MacBook battery life
MacBook Pro Retina 13": up to 7.4 hours extra
MacBook Pro Retina 15": up to 5 hours extra
MacBook Air 11": up to 12 hours extra
MacBook Air 13": up to 13 hours extra
USB Device battery life
iPhone 6: up to 75 hours extra
iPhone 5s: up to 80 hours extra
iPad Air 2: up to 22 hours extra
Galaxy S5: up to 50 hours extra
Nexus 5: up to 127 hours extra



Built-in 60Wh battery pack composed of rechargeable lithium-polymer battery cells

$220 U$


Not too bad....