Photoshop's - RM 3D Extrude FX PSD 6872083
PSD
This is original author's FX adding minimalistic 3D extrusion FX to any custom Text, Shape or Isolated Raster Shape in Photoshop via Smart Object's content change.
Document size is standard A4 Sheet (210mm x 297mm) 300 DPI 3508 x 2480 pixels
Using Smart Object content replacement - you could easily replace Texts, Shapes, or isolated raster shapes to get them as 3D Shapes with Realistic Extrusion and Outer Shadow as you see on preview image applied on demo text.
After changing text or shapes you could merge all in single layer. The shadow layer also will be transparent which is good for PNG export.
Rich customization
You could change your extruded shape color via editing it's Styles
You could select Various Extrude Height presets
You could change background color via editing it's Styles
You could change even shadow color via editing it's Styles
You could reach various color and visual look combination
You could turn off and use just extrusion or just shadow layer