The resulting Rumble Go is as portable as can be. Made of food-grade stainless steel and BPA-free silicone, the durable, dent-resistant, and dishwasher safe components can fit into your existing water bottle. It takes just a minute to set up and then it steeps while you sleep. With no heat or extra gear required, it’s perfect for overnight travels and everyday commutes. Since cold water extracts 70% less acid than hot water, your coffee will taste smoother and sweeter, too.