Most label styles associated with Autodesk Civil 3D objects contain property fields with modifiers. These modifiers are abbreviations for the values you specified for the label property.
The following is a key to the modifier codes:
| 
 U =  | 
 Units  | 
 S =  | 
 Sign  | 
| 
 F =  | 
 Format  | 
 D =  | 
 Direction  | 
| 
 P =  | 
 Precision  | 
 C =  | 
 Capitalization  | 
| 
 R =  | 
 Rounding  | 
 O =  | 
 Output  | 
| 
 A =  | 
 Decimal character  | 
For example, the following is a parcel area property field:
<[Parcel Area(Usq_m|P2|RN|AP|Sn|OF)]>
The following lists each of the modifiers for this label property: