What do you get when you tell a group of former Apple engineers to design a water bottle that's different and better than the rest? You get The Square. It's unique but we're not sure if it's better than other water bottles. The top and bottom cap unscrews for easy cleaning. The caps are made of BPA-free plastic and the bottle body is made of food grade stainless steel. You can hear an audible click to let you know that you've closed the cap tight enough. Maybe not the best water bottle you can find but certainly one of the best looking. Guaranteed for life.