DIY Combination: There are 54 Building blocks including 5 solar panels. You can make Solar building blocks light sign: such as for arbitrary combination into MARRY ME, U&M. Perfect to display on wedding engagement birthday parties bar Christmas festivals etcEnergy-saving & Durable: The module is automatically powered by solar energy, no external wiring is required, and the setting is simple.AUTO ON/OFF FROM DUSK TO DAWN:Keep switch in the ON position before use. Built-in sensitive light Sensor, Automatically Turns On at Dusk and Off at Dawn. No Need to Operate ON/OFF Switch Again and Again Once Put it Into Use, Bringing You Great Convenience.Waterproof: IP65 Waterproof Design. After the Upgrade, Imported ABS Material is Adopted to Make The blocks More Tough and Anti Aging.