The Platypus Hoser has all the things you want from a hydration system. It is made from taste-free & BPA-free plastics. The bag has a food-grade liner that is attached to a tough but pliable outer. What is really cool is the silver ion antimicrobial treatment that keeps the bag fresh & reduces bacteria build up. However, what we recommend at Trekitt, & what all of us do in the shop, is store our hydration packs in the freezer which prevents any build-up of mould or bacteria. The Hoser is Lightweight & versatile. The threaded hose attachment means it is compatible with any of the Platypus threaded lid drinks bottles. It has a easy to use lapel clip that makes it quick to attach to your bag strap & the Hyperflow bite value, which has the fasted flow rate on the market, makes it easy to drink on the go Taste-free & BPA-free for clean drinking. Food-grade liner with rugged exterior is pliable & durable. Silver-ion antimicrobial keeps it fresh. Hydration hose with lapel clip & Hyperflow bite valve makes it easy to drink on the go. Screw-top closure stands up to rugged use.