Like the other two screw gauges, the metric thread gauge #2 (8 mm to 14 mm) does the job. I checked out the other two more closely, mainly because I've used them a lot more than this model. I find it much easier to sort larger machine screws by appearance alone, especially when I have a well-known example. So I don't need it as much as SAE and small versions of Metric. This model works perfectly and does what it is supposed to do. Like the other two, it's about 1/8 inch thick, which is enough to check thread pitch. I think it will last a long time if I take good care of it.