Specifies the current isometric plane.
Summary
The isometric plane affects the cursor movement keys only when Snap mode is on and the snap style is Isometric. If the snap style is Isometric, Ortho mode uses the appropriate axis pair even if Snap mode is off. The current isometric plane also determines the orientation of isometric circles drawn by ELLIPSE.
You can cycle through the isometric planes by pressing Ctrl+E or F5.