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.PLT File Extension

File Type 1	AutoCAD Plotter Document (Most common)
File Format	File
Common?	No
File Description	Vector-based plotter file created by AutoCAD drawing software; can be printed using a plotter, which prints images using lines instead of dots; based on the HPGL format.
Program(s) that open plt files	Windows: Autodesk AutoCAD; ArtCut Pocket PC: Pocket PC CAD (DWG/DXF/PLT) Viewer

File Type 2	HPGL Plot File
File Format	Standard File
Common?	No
File Description	Plotter file based on the Hewlett-Packard Graphics Language (HPGL); used by various drawing programs for creating printable plotter documents; can be scaled to different sizes without losing quality.
Program(s) that open plt files	Mac: IMSI TurboCAD Windows: IMSI TurboCAD; Autodesk AutoCAD; Autodsys IntelliCAD with HPGL Import plugin; CADSoftTools 2D/3D CAD Viewer; Trix DrawingCenter; IrfanView

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