designer's own words:Green tea’s main ingredient is catechins. It is a safe and stable within 60 to 70 degree Celsius. However, if it is heated to higher temperature and brewed longer, another substance called tannin comes out. Tannin is easily combined with catechins as well as other essential substances in our body such as calcium and iron. As a result, tannin prevents our body from absorbing those substances. Therefore, the temperature should be checked properly to appreciate true taste of green tea. it is the best way of drinking green tea if the tea bag would be removed after letting the tea steep for 2 minutes at the temperature of 80 to 90 degree Celsius. teabag is made from natural green tea leaves so that it can be decomposed easily in the environment. Wrapping itself does not consist of more than one part so that it can be opened up as if it is a folded green tea leaf. In other words, no trees need to be cut down in order to make clean white wrapping paper. Thus, the product appeals to our emotion by using left over green tea leaves after brewing tea.