I put a Pro XL ICU in an Ortlieb Atrack 45L backpack. It was used daily for the past six weeks and went from Svalbard to Tanzania to Kenya and back. It held a Nikon Z9 & Z8, 1.4x & 2x converters, 14-24, 24-70, 70-200, 180-600, multiple batteries for both cameras, chargers and several sizes of filters perfectly. It protected the equipment during 21 separate flights, untold kilometers bouncing around in the back of safari Land Rovers, several tuk tuk and taxi rides, and a thousand kilometers onboard a ship and in the bottom of zodiacs. The whole time it has worked flawlessly in some very demanding conditions. Getting lenses, bodies and all the other stuff in and out of it, has been easy. I'll be ordering another one soon for my other Atrack backpack to hold another Z9, 600 f4., 100-400 and a 28-135. I have no doubt that it will work perfectly and protect this set up as well.