These panels come to us from Voltaic Systems, makers of excellent solar-powered bags and packs. These are waterproof, scratch resistant, and UV resistant. With a high efficiency monocrystalline cell, they output 6V at 180 mA via 3.5mm x 1.1mm DC jack connector. The substrate is an aluminum / plastic composite, specifically designed to be durable and lightweight. They can easily stand up to typical outdoor use including being dropped and leaned on. They're very high quality and are perfect for outdoor projects.