Usually while placing any member in ProStructures, we use Level to assign that particular element to a valid Level. It can be assigned either Configuration file value (in Options > Configuration / Isometric Views > Level) or the other Levels from Level Manager.
But this level can also be called via Part Description. Sometime user customize the Part Description file ("pro_st3d.fdt"). This file is located generally in For CONNECT Edition: Drive:\ProgramData\Bentley\ProStructures CONNECT Edition\Configuration\WorkSpaces\USA_Canada_Metric\Standards\ProStructures\Data
Please note that in ProStructures for AutoCAD version and Power ProStructures Version, this file name extension is different and that is "pro_St3d.fdf" which is changed in CONNECT Edition as "pro_st3d.fdt" and the file location is For ProStructures for AutoCAD Versions: Drive:\Program Files\Bentley\ProStructures Ss6 R1\AutoCAD 20xx\Localised\<Your Localization>\DataFor Power ProStructures: Drive:\ProgramData\Bentley\ProStructures V8i S8\WorkSpace\ProStructures\Localised\<Your Localization\Data
One example of Part Description file with inclusion of levels and color is as below
If you look into the image you can see there are three sections in the Syntax
[Part Description name] [Layer definition with line type and line color] [color and linetype definition for 2D drawing]
This file can be freely extended and then as mentioned here we can call color and line type in both modeling and drawing production via this description file. This document will explain how to activate this Part definition level and color working while modeling or placing shapes in model.
Please follow the below steps to activate this Part Description entities in modeling.
1. Go to backstage File > Settings > User > Global Settings.
Under the Options page, check on the Assign description level.
2. After activating this, when you place element, that will follow the level from Part Description file. See one example below.
So in this way, one can use Part Description file to assign level via Description.