Feed the caffeine-loving mad scientist within, with the OXO Cold Brew Coffee Maker. Resembling something you might find in a chemistry set, this slightly transparent tower has one mission and one mission only...to brew you a delicious carafe of cold brew concentrate. To begin the process, simply add 10 oz (or 3.5 cups) of your favorite ground coffee. Pour 40 oz of water over the Rainmaker top for full water dispersion. Gently stir and let your concoction "steep" 12 - 24 hours, or overnight. In the morning, simply place the glass carafe under the cold brew tower, flip the Brew-Release Switch and, depending on the size of your grind, allow approximately 20 minutes for your fresh concentrate to fully drain. Use the carafe stopper to easily measure out 2 oz of freshly brewed concentrate and mix hot or cold water or milk to create your favorite drink.