Solar Charger Keyring
Having something like this solar charger on your keychain is a good way you'll always have it handy when you need it. It's small, but it's always a constant source of power.
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Implications - Eco-conscious consumers are constantly searching for innovative green products to adopt into their lifestyles. Products like these that promote alternate and renewable sources of energy are functional, and also help reduce consumers' carbon footprints.