solid and strong material. unfortunately the screw doesn't tighten properly, so the phone is always dropping the angle.
This clip seems well-made. The jaws are tightened by a thumb screw and grip the phone securely. But I would have preferred spring-mounted jaws because that would be more convenient than a thumb screw. The jaws are deep enough to grip my phone. They are almost deep enough to grip my GPS receiver securely. (The GPS receiver is thicker than a phone.)