Osprey have decided to lay the old Mutant to rest & redesigned this classic climbing pack so it is simpler to use & even more versatile than before! For those of you who owned the pervious Mutant 38 you will understand when I say it was just a bit too fiddly; the floating lid never really sat right on the pack if it wasnt full to the brim & was just awkward to adjust/remove. It had those tiny side pockets too that you couldnt fit any thing in! What were they for? So what Osprey have done to the lid is actually really simple. It is still an adjustable floating lid but it has quick release buckles at the adjustment points, just like the closure buckles; 4 quick squeezes & its off. Done. The main problem with removing the lid of a bag is it makes the bag is not as weatherproof...not with the new Mutant 38. Osprey have chucked on a Flap Jacket Lid closure to maintain the weatherproof qualities of a lidded pack but giving you more head manoeuverability when looking up & searching for holds. Those annoyingly small side pockets have been replaced by ski carry slots for when you fancy a bit of ski mountaineering & the back panel has a lovely smooth finish for easy snow shedding qualities. The back system now has a removable HDEP frame sheet with an aluminium stay to stiffen then packs structure & maintain its shape, & the mesh backing & channeled EVA die-cut padding & shoulder straps improve breathability for summer use. Gone are the old walking pole & ice axe loops! they have been replaced by the easy to use Tool Lock system that can attach you poles or your axe. Simply pull on the metal peg & slot your poles in & clip the tops in place or thread the peg through your axe heads & clip on the handles. The hipbelt still has all the ice clip slots & gear loops & when not in use you can just reverse clip it to keep it out of the way. This is an all round great climbing pack that has had years of feed back from its users to make it even better. Sternum strap with emergency whistle Top lid access Flap Jacket top cover for use without lid Integrated ski/climbing helmet storage Removable top lid with dual compartments Dual Tool Lock for ice axe attachment 15mm side compression straps Abrasion resistant PU texture to front panel Glove friendly buckles Integrated gear loops on hipbelt Internal hydration sleeve Internal key attachment clip Removable HDPE framesheet with T6061 aluminium stay Sewn in hipbelt, reverse wrap stowable Side ski carry Underlid rope carrying system