This 3D model was originally created with Sketchup 13 and then converted to all other 3D formats. Native format is .skp 3dsmax scene is 3ds Max 2016 version, rendered with Vray 3.00 Tree Trunk Stairs I saw on Architecture %26 Arts... Created with 12' 1-1/8Plateline and 22-3/4 Floor Trusses above. 22 Risers @ 7-5/8"