I have a Deuter AC lite 26. In terms of size and weight, it is suitable as a carry-on backpack as far as I know. At least in most airlines it seems. However, this backpack has metal strands in the back. These can't be detached and are used to prevent the backpack from touching your back in order to avoid heavy sweating. So I was wondering whether they could potentially not let me onto the plane with this.
Whether this matters or not, the airlines in question would be