Where to find it:
Main Window / Objects / Subdivision /
Main Window / Extension Pack / Objects / Subdivision
Object Palette / Right Click / Subdivision /
Shortcut: (unassigned, use "Edit / Shortcuts" to assign)
On this page
The Subdivision Control Options allow you to set your all objects or all visible objects to their highest or
lowest available subdivision level if they have OpenSubD applied to them.

Will set all unlocked objects in your project to their highest available Subdivision Level.

Will set all unlocked objects in your project to Subdivision Level 0

Will set all unlocked & visible objects in your project to their highest available Subdivision Level.

Will set all unlocked & visible objects in your project to Subdivision Level 0