CamelBak BFM 500 Denier Hydration Syste is 6.5L larger, but over 1lb lighter with the improved functionality and comfort for carrying the heavy loads. Improved Shoulder Harness and back panel for better load distribution and weight reduction. Fleece-lined glasses, goggles, and NVG pocket with external access. Lightweight, durable 500D Cordura Full Clamshell opening makes adding the MedBak Insert quick and easy (sold separately). Lower drink tube exit ports for under arm tube routing. Dual ASIPS antennae ports.