Rating: 5 / 5
I received my Zpacks Arc Blast, the large 60 liter, 17.0 oz. size for winter loads, and love it. If you are worried about getting poked, don’t worry, the stays terminate at the bottom end BEHIND the hip belt, and can in no way poke you in the back, or the side, or anywhere else. I loaded it with several large, smoothly rounded Tide soap containers, totaling 42 pounds, and it carries very nicely, transferring weight to the hips: you can put 100% of the weight on the hips, or by loosening or opening the hip belt you can put 100% of the weight on the shoulders.
The stays are not round, like arrow shafts, but flat, like the whalebone slats in my girdle… oh… never mind about that. The mesh trampoline exists only in the middle 3/4ths of the back, and bears no weight. It is a couple of inches away from the pack, the exact amount depending on how much arc you put in the flat stays, which are easy to adjust. The bottom of the pack itself is what sits on your body’s back shelf, formed by your lower back and hips.
Of course, there is no way that Yours Truly is going to actually carry 40 lbs of winter gear: that is a job for the Little Wifey and our 3 Ankle Biters. I will then set up the tent, and tie the guylines around their waists, and they will sit up all night holding the tent down, while I get a little much-needed shut eye.