Mechanical discipline is an application capable of placing HVAC and plumbing components from a vast database of manufacturer catalogs. Dimensions and data attached to Bentley mechanical elements in the DGN model represent actual products commercially available to engineers and designers. Custom designed fittings, duct or air handlers are placed without catalogs as well. These types of elements are generated inside the application using the datagroup system's capabilities. Custom elements are then exported to third party manufacturing applications such as FabShop fabrication. The Trimble^® FabShop software has ability to export and import fittings using the Bentley i‐ model technology. Modification and manipulation tools provide ways to select new catalog items or to change the physical dimensions of any placed component. Exporting component data interoperable in FabShop fabrication software is achieved through i-model publishing interface.