ERDAS offers a number of solutions in various application areas for users on the ArcGIS platform. These products are geared towards image processing and feature collection.
The ERDAS Extensions for ArcGIS installer contains Image Analysis for ArcGIS, Stereo Analyst for ArcGIS, ERDAS Terrain Editor for ArcGIS, and FeatureAssist for ArcGIS. The installer's menu permits you to selected the desired component. All installations of the ERDAS Extensions for ArcGIS on a given machine must be the same version.