Hydro Flask Standard Flex Cap Black 18 oz

I really like this water bottle for the most part. It keeps my water cold all day, and it fits perfectly in the side pocket of my backpack that I use for work. Some down sides are that it doesn't fit well in my car cup holder, the water takes on a metallic taste if left in there for more than a day, it is heavy, and since it isn't transparent, you can't monitor how full it is and filling it can be tricky. Other than those minor annoyances, it's great.