I take 1 cup of coffee beans, then grind coarsely and put into one of these bags. Then the bag goes into 1 gallon of water for 12 hours and I had the absolute BEST cold brew coffee that I've ever tasted! These cotton tea bags were super inexpensive, arrived really quickly, and do exactly what I needed them to do. There isn't excessive residue when I remove them from the cold brew, which I'm really happy about. I will definitely be buying from here again :)