Superbly well thought-out and built pack. The most customizable and comfortable fit that I have experienced on any backpack. I was unsure of the size I required and Millets website was a little confusing in this regard. The pack marked 'M/L' on the website turned out to be a size Large which was the wrong size for me. A member of staff in the shop found another size on the website marked as '(MEDIUM)' and had that sent instead This was in fact a Medium size pack which was the perfect fit. So, highly recommended pack, but measure your back length as per Osprey guidance and from Millets website select M/L for the large size and (MEDIUM) for the medium size.