Features: The tiny crystals inside the sheets respond to heat by changing color, demonstrating how LCD work in a way that lets you see fantastical patterns safely. You can give these sheets as gifts to your friends, sons, nieces, daughters, or other people you care, which will generate their interest. Specifications: Color: as pictures shown Size: 6 x 6 inch Package includes: 6 Packs of sheets Notes: Manual measurement, please allow slight errors on size. The color may exist slight difference due to different screen displays. Do not expose to direct sunlight, prolonged exposure to sunlight may affect the color rendering performance of sheets.