This polychoron can be obtained as the convex hull of 2 mutually dual pens and one rap of according ratios a, x and b respectively. Edges a and b become internal (pseudo). Only x and the 3 lacings remain. Each cell is a bipyramid on (pseudo) base xee with tip-to-tip distance b.

Incidence matrix according to Dynkin symbol

m3o3m3o =
aoo3obo3ooo3oox&#z(c,d,e)   → height = 0
                              a = 2/3 = 0.666667 (pseudo)
                              b = 4/7 = 0.571429 (pseudo)
                              c = lacing(1,2) = 8/21 = 0.380952
                              d = lacing(2,3) = 3 sqrt(2)/7 = 0.606092
                              e = lacing(1,3) = a = 2/3 = 0.666667

o..3o..3o..3o..           | 5  * * ♦  4  4  0  0 | 12  0 |  6
.o.3.o.3.o.3.o.           | * 10 * ♦  2  0  3  0 |  6  3 |  6
..o3..o3..o3..o           | *  * 5 ♦  0  4  6  4 | 12 12 | 12
--------------------------+--------+-------------+-------+---
oo.3oo.3oo.3oo.&#c        | 1  1 0 | 20  *  *  * |  3  0 |  3
o.o3o.o3o.o3o.o&#e        | 1  0 1 |  * 20  *  * |  3  0 |  3
.oo3.oo3.oo3.oo&#d        | 0  1 1 |  *  * 30  * |  2  2 |  4
... ... ... ..x           | 0  0 2 |  *  *  * 10 |  0  3 |  3
--------------------------+--------+-------------+-------+---
ooo3ooo3ooo3ooo&#r(c,d,e) | 1  1 1 |  1  1  1  0 | 60  * |  2
... ... ... .ox&#d        | 0  1 2 |  0  0  2  1 |  * 30 |  2
--------------------------+--------+-------------+-------+---
... obo ... oox&#(c,d,e)t | 1  2 2 |  2  2  4  1 |  4  2 | 30