【Compatible with Various Filter Straws】This collapsible water bottle easily collects water from lakes, rivers, streams, and municipal sources. It’s compatible with Membrane Solutions, LifeStraw, Sawyer MINI, Micro Squeeze, and most 28mm screw-cap water filters, making it a reliable squeezable filtration system for outdoor adventures. 【Dual Opening Design】 The water bag is a dual-opening design with a slider-sealed wide opening for quick water filling, and a standard water bottle-style screw opening that pairs perfectly with the water filter to ensure that you have access to clean drinking water no matter where you are. 【Premium TPU Material】This water bladder is made of durable TPU material, which is more durable, abrasion-resistant and leak-proof than traditional materials. It will never break even if accidentally dropped! 【Ultra-Light & Collapsible】 Weighing just 2.69 ounces, this 2L water bag is both lightweight and collapsible, providing exceptional portability for hikers and campers alike 【Strong Sealing】Adopting reliable materials and craftsmanship, the water bag is waterproof and leak-proof, and can work normally in hot or cold conditions, so it can seal the internal liquid well to prevent liquid leakage. This water bag is designed to work seamlessly with most water filters such as Sawyer Water Filter SP128/SP129 and so on, making it a reliable replacement to your original water container for outdoor adventures