Everything is clear in Will Heltsley's review. This is a good vise and works well in most cases, but the fact that the machined surface of the jaws is slightly recessed compared to the casting limits your ability to clamp things deeper than an inch as the underside of the molded Part of the jaws touches the workpiece up to the machined section. You can make a thicker pair of machined jaw pads, but that's pretty much the only way to overcome this limitation. If you always drill through parts less than an inch thick then you're fine, or if you can clamp the bottom of the workpiece in the machined jaws and the rest protrudes beyond the vise then that's fine too. It's a neat little device, works well and is reasonably priced, but this limitation needs to be addressed by the manufacturer.