This was included as a set with a trail running backpack, but I'm using the hydration system I already had, so I haven't used this and have kept it stored. I'm selling it because I have no opportunity to use it. Lightweight and durable 2.5L hydration pack with a red bite valve. - Brand: OSPREY - Model: Hydraulics LT - Capacity: 2.5L (85oz) - Bite Valve: Red bite valve - Manufacturer: Hydrapak Thank you for looking.