Up to 18% energy conversion rate, dual 5V / 2A USB ports, Battery capacity: 15000mAh, LED: 180LM (high brightness); 50LM (low brightness).
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Check out price history chart (for all/most countries) for Zanflare WN-157 Solar Charger. The lowest price was: $10.31.
Price records source(s): Gearbest
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You can set price alert (for Banggood and Aliexpress (only if product name will be the same as on Banggood and I will post it on social media though, so it’s more like Banggood price alert)).