The following group codes apply to solid entities.
Solid group codes 


Group code 
Description 
100 
Subclass marker (AcDbTrace) 
10 
First corner DXF: X value; APP: 3D point 
20, 30 
DXF: Y and Z values of first corner 
11 
Second corner DXF: X value; APP: 3D point 
21, 31 
DXF: Y and Z values of second corner 
12 
Third corner XF: X value; APP: 3D point 
22, 32 
DXF: Y and Z values of third corner 
13 
Fourth corner. If only three corners are entered to define the SOLID, then the fourth corner coordinate is the same as the third. DXF: X value; APP: 3D point 
23, 33 
DXF: Y and Z values of fourth corner 
39 
Thickness (optional; default = 0) 
210 
Extrusion direction (optional; default = 0, 0, 1) DXF: X value; APP: 3D vector 
220, 230 
DXF: Y and Z values of extrusion direction (optional) 