I thought the sacoche from another company I had used up until now was a little small, so I bought this one. When I purchased the item, I was considering the shape of the shoulder strap, and when I checked the item I received, I found a round string, so I thought it would interfere with it when used in conjunction with a backpack, so I had been using it so far. I have transplanted a flat string of sacoche. The shape of the string is changed to what you like on your own, but it does not require any pressure to step on it, so it is comfortable to use. thank you very much.