box b 1 1 1
nexplode b f
profile pp x 0.6 y 0.6 x -0.6 y -0.6
ttranslate pp 0.2 0.2 1
featprism b pp b_4 0 0 -1 0 1
featperformval prism r 0.8
vertex v1 0.2 0.5 1
vertex v2 0.8 0.5 1
edge e1 v2 v1 
wire w e1 

plane pl 0.5 0.5 1 0 -1 0
featlf r w pl 0 0.2 0 0 0 0 1 1
featperform lf result 


set square 8.56