Qi Pack's 2L BPA Free Water Bladder for Hydration Backpacks QI PACKS UNIVERSAL HYDRATION BLADDER REPLACEMENT fits most Hydration Packs and Backpacks and Boasts a 2 liter / 70-Ounce Capacity. QI PACKS BLADDER IS BPA-FREE, So You Know You Can Carry a Safe Quality Water Supply. MILITARY-GRADE HYDRATION BLADDER With An Upgraded 4 mm Thick Wall To Provide Continuous Use Without Fear Of Normal Wear and Tear. THE QI PACK BLADDER HAS A WIDE MOUTH, Making Filling And Cleaning Easy, Safe And Worry Free. STAYING HYDRATED MADE SIMPLE! Whether You Are Hiking/ Climbing, Cycling, Biking, Running or Jogging, This High Quality Military Grade Insulated Bladder, Will Keep You Well Hydrated With Comfort & Ease Without Having to Carry Bulky Bottles. 100% SATISFACTION GUARANTEED.