Features:

1.Slide-lock system--get rid of the trouble of opening traditional switch cover.

2.Hanging system for backpack

Stable handle for water bladder

3.Full opening bag design--easy to put your hand inside to clean & make it dry.
 

4.Quick-connect outlet and tube together

5.Bite and suck design
 

* Convenient assembling with backpack: put bladder body filled with water in bag, then connect tube in one second without leaking.