Absolutely completely 100% natural, chemical-free, completely biodegradable (or even compostable), the t-sac #2 is my favorite tea filter. I do not like plastic, silicone, or metal “tea balls” or other infusers. Paper filters can be used for a much wider variety of teas and tisanes, and allow much better flow-through for fuller flavor extraction. While they are very convenient for a single teacup, they are large enough to make a teapot for two or more. 100 bags per box, for most folks that’s enough for 2-3 months of tea!