M-Wave Maastricht H2O drinking backpack This drinking backpack has a 2 liter water bag with antibacterial lining, so your water will always taste deliciously fresh. The large opening makes the drinking backpack easy to clean. The drinking hose is interchangeable, the mouthpiece is rotatable and the reflective effect of the drinking backpack means you can also go out in the evenings. Specifications: Color: black Gender: unisex Material: polyester