K.E.J. Solar Pool Side Lights Color Changing Solar Deck Lights Outdoor LED Step Light Waterproof Pool Accessories Decor for Stairs Fence Yard Driveway Pathway Yard Backyard Garden (16)We changing amorphous (thin film) panels of solar outdoor lights to polycrystalline solar panels, which increases the photoeectric conversion rate from 10% to 17%. FT CTX No bills as per electrical charges or wires. Solar powered lights simply need plenty of sunlight, and light on automatically at dusk and nighttime, off at daytime automatically. Just get them well charged for optimum performance all through the night. No wires required, super easy