This has everything you could want in a vest. I love how the Lateral Micro Adjust System allows me to change the fit with ease between uphill and downhill legs of a run. It hugs my chest so comfortably to limit bouncing. I thought the 12L might be too large for shorter runs where I just wanted to bring water, but I was wrong. The cinching straps on the back tighten up the pack when nothing is in it, but can stretch out to carry a bladder and/or a ton of snacks and spikes on a long day.
I'm so happy with this vest. I particularly like how compact if feels (it is) yet how much you can squeeze into it - enough storage for key running items (hydration, bottles and/or food, space for a phone, and even a few bungee straps on the back for poles, jacket, etc. I love the material (feels soft, but is incredibly durable) and particularly enjoy how well it sits on my body... ie: it doesn't move around. This is an awesome vest!
Great running pack. Supper comfy running 20 miles. I’ll be perfect for 100K