The solar panel does not hold a charge it produces power when it is exposed to sunlight. You can plug your phone directly into the panel or use it to recharge a portable recharger for later use. The Nomad 20 is best used for recharging things like:

Headlamps
Phones
Tablets
Other USB similar devices
Goal Zero Power Pack

Nomad 20 panel works best with all of our small to medium rechargers.

Switch 10 Core 4 Hours
Flip 10 Power Bank 2.5 Hours
Guide 10 Plus Power Bank 2.5-5 Hours
Flip 20 Power Bank 5 Hours
Venture 30 / Flip 30 Power Bank 5-6 Hours
Sherpa 50 Power Pack 6-12 Hours
Sherpa 100 Power Pack 10-20 Hours
Yeti 150 Power Station 17-34 Hours

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