Which file should I choose?
Use Allen-Bradley-440J-N21TNPM-2D-CAD-Block.dxf to insert the supplied editable drawing into your layout. The ZIP contains the unmodified Allen-Bradley-440J-N21TNPM-2D-CAD-Block.dxf.
Allen-Bradley-440J-N21TNPM-STEP-3D-CAD-Block.zip is the original NHP Electrical Engineering Products archive. Open 440j-n21tnpm.stp inside it to place the original solid geometry in your 3D assembly.
