ALLPOWERS Polycrystalline MC4 solar charger has a high-efficiency conversion rate, the transformation efficiency is up to 21%, while most of the similar products on the market are 15% or even lower. Whether you’re charging a generator phone laptop or refueling a power pack, solar power has you covered. Our foldable portable polycrystalline solar panels are rugged, reliable, and easy to use. Harness the sun with portable solar power wherever you are.