✔ A TRULY PORTABLE COFFEE MAKER - Simply drop this lightweight 2.8oz Rumble Go filter into a compatible water bottle, and you've instantly transformed it into a portable cold brew coffee maker. The brewing process couldn't be easier: just add coffee grounds to the filter and water to the bottle, then seal it up and give it a "rumble" (i.e. rotate bottle horizontally 2 times), and your coffee is now brewing! By morning, you'll have cold brew coffee as good as the stuff the pros make. ✔ COLD-BREWING IS THE SIMPLEST WAY TO MAKE COFFEE OUTSIDE YOUR HOME - Now you can make coffee just about anywhere you go, since there's no need for heat or electricity. With Rumble Go you can brew coffee whether you're camping, picnicking, driving, traveling for work or relaxing at the beach. All you need are grounds, lukewarm water and time. Rumble Go takes portable to the extreme. No glass bottles to break. No disposable filters to forget. No fragile parts to protect. No gizmos to charge. ✔ UNIVERSAL DESIGN HAS AN EXTENDABLE BASE THAT FITS MANY 16-32OZ WIDE MOUTH WATER BOTTLES & INSULATED TUMBLERS - Rumble Go’s universal design features an extendable base that adjusts by up to 1.5” to allow it to fit many of the leading WIDE-mouth water bottle and insulated bottles on the market, so it is compatible with bottles made by Hydro Flask, Klean Kanteen, Nalgene, CamelBak, Fifty-Fifty, Mira, RTIC and more. See the compatibility list in the image gallery for more info and tips for measuring your own bottle. ✔ A FILTER DESIGNED FOR STRONGER COLD BREW COFFEE - Stainless steel filter was designed by cold brew experts to make professional-quality coffee. The 18/8 stainless steel filter features 200 micron holes, the ideal size for allowing water to circulate & optimal extraction to occur with coarse-ground coffee. It’s a radical improvement to those first-generation cold-brew kits with fine mesh or paper filters, which were originally designed for brewing hot coffee. You’ll taste the difference. ✔ DURABLE, ECO-FRIENDLY & DISHWASHER SAFE – The type 304 stainless steel filter is shockingly lightweight (2.8oz incl. cap + base) but sturdy & dent-resistant. The food-grade silicone cap & base are BPA-free and act as shock absorbers protecting your bottle & filter from dings during movement. Eco-conscious design means no disposable filters, no plastic parts and a very minimal packaging footprint. All 3 components can be easily separated for a quick rinse or washing by hand or in a dishwasher. Rumble Go could be the world's most portable coffee maker. Just drop this reusable cold brew filter into a compatible water bottle, and you've instantly transformed your bottle into a portable cold brew coffee maker. The brewing process couldn't be easier: just add coffee grounds and water and give it a "rumble" (i.e. rotate bottle horizontally 2x), and your brewing has begun! The good news is that you likely already own a compatible insulated stainless steel tumbler or WIDE mouth 16-32 ounce plastic water bottle that works with the Rumble Go filter. That's because this filter was built with a universal, height-adjustable design that allows it to extend 1.5" so that it fits a wide range of the most popular water bottles on the market. You can see a list of compatible bottles in the image gallery. No need to buy another single-purpose container just for your coffee. You can just repurpose an old one for a more eco-friendly alternative. The filter has been forged from 18/8 stainless steel that's durable and lightweight, and its 200 micron holes were specified by the experts for use with cold brew's recommended coarse grounds. There are no disposable paper filters to buy, and no fabric filters to clean and dry. The Rumble Go disassembles for super quick cleaning, and it's also dishwasher safe. Get ready to make barista-quality cold brew coffee anywhere you go, whether you're commuting in your car, at your desk at work, at a picnic in the park, or heading out for a weekend camping. Remember: cold-brewing is the easiest way to make coffee when you're away from home, since you don't even need a hot water source! Now you can wake up to a ready-to-drink coffee vs having to figure out how & where to either buy or brew a hot cup. It's the ultimate format for coffee on the go. Crowdfunded on Kickstarter. Made in Taiwan or China. Includes an 18/8 stainless steel (type 304) cold brew filter and a food-grade silicone cap & extendable base in 2 colors: Orangey-Red and Dark Black.