The 321 Water bottle is a reusable personal water filtration bottle with a unique plunger filter mechanism invented by Charlwood Design. The ecologically sustainable design encourages the environmentally conscious user to carry and refill the BPA-free bottle and the carbon filters are easily replaceable. They can be plunged repeatedly to filter the water. Most refillable filtered water bottles use gravity to slowly drip filtered water into a cavity. The innovative ‘plunge filter’ allows the user to filter the water by pressing down the unique stem and fills the entire cavity of the bottle with freshly filtered water. The result is a beautiful, elegant product designed with sustainable principles in mind.