This is an easy-to-use Platypus hydration system with a 1.5L capacity. - Brand: platypus - Model Name: BIG ZIP LP - Capacity: 1.5L / 50 oz - Includes: Hose and valve I bought this a few years ago because I was invited to climb Mt. Hotaka, but I couldn't go, and it's been stored ever since. It is unused. The case has a few dents and stains. Thank you.