Parameters: Material: metal + plastic Features: it is suitable for roll tobacco and cut tobacco, besides, you can add some tea leaves or drinks you like to create different flavors. You can put some rice in it, no water required, just give it a try. Removable and easy to clean. Aging: it is reusable, and you just need to change water. Filtration principle: long time ago, our ancestors found that water as a medium can play a role of filtering, it can effectively filter the tar, nicotine and a carbon acid of the cigarette, which can alleviate the symptoms caused by smoking such as phlegm, significantly reduce the scale on the teeth.