CCAD
Weldsym
Trial versionAutoCAD Tool Simplifies Welding Symbol Creation
WindowseDucts
Trial versioneDucts Simplifies Round Ductwork Design in AutoCAD
WindowsSteel Shapes for AutoCAD
Trial versionAutoCAD Tool for Drawing Steel Shapes
WindowsPfast
Trial versionPfast 2.1: Streamline Hole and Fastener Creation in AutoCAD
Windows