The Source Streamer 3. 0 Reservoir will fit in any Deuter pack designed for three liter reservoirs and many other hydration packs as well. Deuter has chosen not to make their own bladder, but source their bladder from Source, an Israeli company. Deuter has been working closely with Source to perfect their Streamer Reservoir. The result of this effort is represented with the all new Helix Valve. The new mouthpiece has a water stop tab and is absolutely drip free. Only light pressure is needed to activate the water flow. A spring integrated within the valve ensures instantaneous shut off of the water flow as soon as the valve is released. The Dirt Guard cap covers the valve during transportation to keep things tidy. But regardless of precautions, mountain bike equals dirty, so the Helix Valve was designed to easily be disassembled and cleaned. The reservoir itself is made from a BPA free polyethylene PE plastic that boasts a surface as smooth as glass. Smooth is important because the smoother the surface, the harder it is for bacteria to attach itself. In addition, the surface makes it harder for taste, like old Cytomax, to remain after it the bladder has been washed. Beyond the glass like surface, there's Grunge Guard, an anti microbial coating designed to further keep mold at bay. Sealing the system is a bar and clip system that allows the bladder to be both opened completely and sealed completely, and is tough enough to be landed on. Deuter says the reservoir is so well sealed that if you take out all the air after filling, you can probably leave the sack filled with liquid for a few weeks without growing mold. We don't want to try, but know that some of us are forgetful. Even when the Source Streamer 3 Liter Reservoir is dirty, washing with mild dish soap and warm water under 140 degrees Fahrenheit is enough to clean out the muck. For sterilizing, clean, dry with towels, and leave everything in the freezer overnight. Flush with water in the m...