Rumble Jar: Quart size (32oz), includes Mason jarNow you can make barista quality cold brew coffee at home. Rumble Jar is an award winning cold brew coffee maker, designed to work in tandem with the classic Mason jar. This 4 piece brew kit is all the equipment you need to make professional grade cold brew coffee right at home. Just take your favorite coffee beans, grind them coarsely, add tap water and give it a rumble. Total prep time takes less than a minute, and by the morning you'll have