Size: approx 45*45cm (17.7 * 17.7 inch)Inner material: Bamboo CharcoalSurface material: synthetic fibreCharcoal is a pure natural product and it is non-toxic, tasteless, no side effects to people.If the ambient humidity, it can absorb water, if the surrounding environment is dry, it can release water.Charcoal is a good material.Package including 1 x seat mat