The Source Convertube and Filter is a tube attachment that turns (almost) any bottle into a hydration system.  But wait, there's more.  It comes with a fitted in-line filter, which means you can refill your bottle from a creek or other water source.  

The Filter

• Sawyer Mini Filter eliminates 99.99% of bacteria and protozoa
• filter can be backwashed a reused over and over
• no replacement cartridges needed
• no chemicals needed

Convertube adapters

• 24mm (e.g. Evian bottles)
• 28mm (e.g. standard PET)
• 42mm (e.g. Sigg bottles)
• 63mm (e.g. Nalgene bottles)

Specifications

• tube length: 94cm
• inner tube length (inserted into bottle): 35cm