Exactly what I was looking for. I researched top tube bags extensively, most smaller bags would not fit my iPhone 15 max with an otterbox defender case. The shape and size of this bag is perfect without being overwhelming on a small frame. Will hold the phone, a few other small items like gels in the side pockets. Will use in conjunction with the Chrome waterproof rolltop handlebar bag. A great combo for gravel. Look forward to a bolt on version in the future.