Plunge : not necessary PVC tube because with 20mm plunge set and sing 4 mm.router the dimension of the plunge will be 10 mm,if
I'm not wrong. ( in my tests this result is confirmed).
Thanks now I know that 6 mm. is the minimum fence heigh ! it's a pity when you work on thin pieces - suitable for use with 4 mm.
dominoes.
Thanks to all for answers. I'm a beginner in the Festool world.