Three Rucksacks in one! The Rocket Pack can be used when fully zipped together using all available 70 liters 4270 cu.in. It can also be used as a smaller 40 liter2440 cu.in. rucksack by unzipping the two detachable side pockets (rockets) at the side of the pack. However if a smaller day pack is needed by zipping the rockets together using the small additional yoke harness (available as an optional extra) a smaller 30 liter1830 cu.in rucksack can be made. Zip on detachable side pockets arepatible with army issue yoke. All harnesses and back system are air mesh padded for extrafort when carrying. Special Features : 40 liter 2440 cu.in. Centerpartment plus 2 x 15 liters 915 cu.in. detachable pockets - 70 liters 4270 cu. in Outer lid pocket and Inner lid pocket 2 mesh storage side pockets Under pack pocket w2 waterproof nylon covers one camo and one desert Adjustable chest strap Adjustable waist strap Contoured shoulder harness Adjustable Internal Frame