CamelBak Octane 18X 100oz Hydration Pack. The CamelBak Octane 18x 100oz Hydration Pack is the perfect means to carry ample gear and fluids for 3 hours of adventure out on the trails. The 100oz Antidote reservoir has your hydration needs covered while the 915 cubic inches of expandable gear space offers room for all the nutrition, tools, electronic devices, and extra clothing needed for extended endeavors in the woods. Its highly ventilated Air Mesh back panel and Ultra Lite Independent Suspension harness ensure superb comfort and ventilation while the pack's ultra light materials mean you remain nimble and agile out on the trails. For safety, there's a whistle on the harness as well as reflective accents both front and back for enhanced visibility.