Exercise illustrations are a bit confusing, but you can figure it out on your own quickly. It is a solid product.
My college grandson loves it, he always has problems with breaking zippers and the top opening is great.
The kidney strap holds tight (if you thread it properly cause it slipped through the first time he used it). My goto travel pack from now on. I can't speak for it's lifetime existence because I've only had it for a few weeks, but what I've seen, it'll holds up. Overall, we're pleased. The fabric is quality made. My husband put a ton of heavy books (80lbs) in it and went for a Ruck March and it' held up fine.
It worked well and easy to wash away the sand. Strong and is comfortable. The beach I go to has a lot of stuff on the sand so I don’t like to swim without something on my feet.
I'm 5'10" and weighs around 162 lbs but i ordered M as described for the height and weight. It's somewhat large and not very comfortable as sports fit.