【Advanced Technology】With advanced filtration membrane technology, this filter straw is divided into four stages, including pre-filter, coconut shell activated carbon, hollow fiber ultrafiltration membranes, etc.It is capable of removing all visible solid sediments, and improving the odor, ensuring water in the worst environments.【Tritan & BPA Free】Tritan constitutes a BPA-free filtered water bottle, which is food grade material.It does not produce any harmful substances or bad odors to guarantee the safety of your drink and the good taste of the water.【Daily Use & Wild Survival】Portable The filtered bottle weighs only 22 ounces, it is very easy to carry.More importantly, it can transform lakes, rivers, springs, streams into drinking water to keep energy out.It is ideal for travel, hiking, camping, backpacking, fitness.【Kind reminder】Rinse the carbon filter with water less than one gram to remove the taste by itself when first used.And vacuum 4 to 5 times to bring the water up through the filter.RATICAL AND UNIQUE DESIGN This mug has excellent dual-use function.When you remove the filter inside the cup and change it to a straw, it becomes a sports cup.The cup cap and push-button lock prevent leaks.Portable, durable and easy to clean.