I use the same system and I have never seen those. I imagine you can put those on top of the impression and then trace them with a fine tip marker to ensure proper alignment?
They are for putting around the form which is the base of the model so that the stone doesn't fully encapsulate the form. Put them at the top of the hole where the stone goes.
Very important on the full arch to keep the stone from creeping over the palate of the base.. however, Ive used monotrac for years and never seen that, even on the website.. maybe its new..
They've had those for a while. I think they usually come with the trial kit.
You put it over the impression and mark an outline with a sharpie on the impression so you get the same alignment with the base. Useful when starting out with the system.