About Defining Prefix and Suffix Values of Thickness Dimension
You can use the following Detail options to define the prefix and suffix values of thickness dimensions in 3D mode.
• default_thickness_dim_suffix
• default_thickness_dim_prefix
The Dimension tab opens when you click the dimension. The set values of the above options are displayed in the Prefix and Suffix boxes in the Dimension Text panel that appears when you click Dimension Text group on the Dimension tab. You can modify the prefix and suffix values.