Files with the .DWL extension contain information about blockades relevant to a particular opened drawing project. It is created, used, and deleted by the TurboCAD software, which assists in 2-dimensional and 3-dimensional design. The information contained in the file prevent the simultaneous editing of the project on more than one instances of the software, this way preventing the files from becoming corrupt.

A DWL file is created when one attempts to save a drawing file opened in TurboCAD; when the drawing file is closed, the blockade file is deleted automatically.