Building A Better Cold Brew Coffee Maker
The Filter. We engineered an entirely new filter designed specifically for the cold-brewing process. This is not one of those run-of-the-mill cheap mesh filters originally designed to brew hot coffee and then just repurposed for cold brew. Instead, our filters are etched out of a single sheet of 18/8 (Type 304) stainless steel, which makes them lightweight but shockingly sturdy. They're designed to last for years and are a total cinch to clean. Most importantly, the filter's 200-micron hole size allows water to circulate at an ideal rate for steeping coffee that has been ground coarsely, which is the same way the pros make cold brew. This filter is also flexible enough to allow a person to brew with medium-size grounds (commonly found in pre-ground packaged coffee). This filter contains no plastic parts, and it does not require disposable paper filters or reusable felt ones that are a pain to wash and end up costing you money to replace later. Those paper/felt filters just soak up the flavorful oils that are the hallmarks of good coffee anyway, so you won't miss them.
The cap. A patent-pending, FDA-approved, food-grade silicone cap allows the filter to be fully contained inside a Mason jar or water bottle, which keeps it out of the way so it doesn't interfere with the jar/bottle's original seal. As a result, your container stays leakproof and your coffee brews in an airtight chamber. An airtight chamber prevents oxidation (aka the "coffee killer"), so the bottom line is you'll end up drinking better-tasting coffee. The cap's shock-absorbing design also protects the metal filter from dents and rattles, helping ensure it can last for years.
The Extendable Base (*found on the Rumble Go only*). The Rumble Go's silicone base features 11 different height adjustments that extend the filter by up to 1.5" so it can fit a wide range of popular 16-32oz wide-mouth bottles. The universal design means you can keep using your favorite water bottle or repurpose an old one that may have fallen out of use.
The Mason Jar (*for the Rumble Jar only*). An ideal 3-in-1 brewing + drinking + storage vessel with a legendary seal. Our patent-pending design ensures that this legendary seal stays intact as originally designed, allowing your coffee to stay fresher since the jar remains airtight and resists oxidation. Of course, a good seal also keeps it from leaking all over the place. And if an accident happens and you ending up breaking your jar, the good news is how easy and cheap it is to replace a Mason jar. No need to shell out for an overpriced, proprietary piece of glass.
Want to see it in action? Watch our 92-second video
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