Snugpak Force 35 Rucksack - Sumo Survival - Bushcraft UK
Designed to be used alongside the Response Pak the Force 35 is a very well made piece of kit. Side pockets will easily fit a 58 style water bottle and use drawcords instead of zips, I found this good for cook kit but be careful with small items. The rucksack sits a bit higher on your back to accommodate the response pak which is a good feature, they work well together. With plenty of padding I wore this for a few hours fully packed with ease. Whilst a little bit pricier than others its worth spending the extra twenty quid!