This is a pen holder that snaps into the dewalt router plate that is standard for the low rider V2. Just pull out the router (or retract it if you have a short pen) and snap in the disc from underneath. Compatible with my Z-Probe so it will know where the pen height is.
I highly reccomend printing this in PETG or armadillo/nylon.
I like this design since the pen is where the cutting bit normally is, you can preview where cuts will be with your pen and also use it to draw a positioning grid on your table with the cutting extent of your setup.
Inspired by alted's pen holder and also those little plastic discs that go inside 45 records (ask your parents).