This 0.5W Solar Panel is a monocrystalline silicon solar panel, which is the main trend in the future. Comparing to polycrystalline silicon solar panel and thin-film solar panel, monocrystalline silicon solar panel performs a higher conversion rate that up to 17%. The surface is covered by the fine resin which makes it waterproof, together with a very sturdy back, it is really suitable for the outdoor environment.