Happy and Hydrated
"Finally, I can write my review of this very fine product. About 4 months have gone by since I ordered a new hydration system from Cascade Designs, producer of the Platypus line of hydration products. I needed a replacement for a much older Platypus system that I began using 26 years ago. In all that time the reservoirs never leaked, the plastic never developed a "taste", and I still have all my original and functional bite valves. It was the screw-on caps that eventually failed. Lucky for me the company is still in business and has improved their product line fantastically. I purchased two of the Big Zip EVO Reservoirs, one 1.5-liter and one 2-liter capacity. I ride a long wheel based recumbent bicycle with a day bag strapped to my seat back that holds the Big Zip bag perfectly. Everything still fits where it was placed before. The supply tube is a larger diameter and combined with the valved bite valve it supplies a larger volume of water on demand. Here in the desert that is useful. It's also nice to have a removable supply tube that easily separates from the reservoir connection, leaving it drip-free. At the top of the reservoir there is the Big Zip zipper that has a separate runner to attain a tight seal when installed over the zipper. The runner is bungie-corded to a plastic framework mounted on the reservoir that you can pinch to hold the zipper open for filling and draining. Very convenient, and it aids in positive control of the reservoir while filling. No spills! When you're done for the day, you can drain the reservoir and lodge the runner inside the zipper opening to hold it open for more effective drying. In all, I am totally pleased with the quality and function of the Big Zip EVO system. One more feature to mention, the plastic reservoir has been treated with an embedded silver ion for to eliminate mold and bacteria. All this, and they still have a limited lifetime warranty. I'm happy and hydrated."