Most people love the convenience of the wide mouth bottle when it comes to filling and cleaning but sometimes find it hard to drink from. The Easy Sipper solves that problem. It fits snugly into the neck of the bottle and your beverage flows out in a nice controlled flow. It's then easy to pop the Easy Sipper out to clean or fill your bottle. Dishwasher safe. Fits 32oz Wide Mouth Nalgene bottles only.