The first level of electronic height gage functions very similarly to a mechanical height gage. They will have a comparable level of accuracy to a mechanical height gage. Additionally, these will include both a floating and an absolute zero, data output, and data unit conversion. The second level of electronic height gage builds upon the first group. This level will have an increased degree of accuracy, and might possibly come with more advanced features. Some of these features could include a tolerance setting, a maximum and minimum setting, TIR compensation, ID/OD measurement, or a probe compensation. Finally, the third level of electronic height gage contains all of the features of the first and second level, with higher accuracy and more features. The additional features you will likely see in this group are a motorized touch probe, a computer interface, air bearings, and the ability to store part programs.