-Special material, safe and non-toxic. -Provide the feeling of natural environment, vividness and color details add vivid life to your aquarium. -Provide shelters, hiding places, and entertainment venues for fish and other animals. -Perfectly fill the vacancy of the fish tank and make it more beautiful -If you have any questions about product transportation or use, please feel free to contact us, professional customer service will give you a satisfactory answer within 24 hours