An additional adjustable thrust wheel, moving along the horizontal shelf of the top rail, serves to prevent the door from moving upwards when moving – skewing, or door jumping. Roller can be used both with symmetrical and asymmetrical vertical profiles in Standard and WAVE systems when installed with a visible track.

It is recommended to use this roller for the structures which can skew during movement:
Light weight doors less than 15 kg
High doors when height to width ratio is more than 4:1
Narrow doors less than 600 mm wide

More information is available on ARISTO website https://www.aristo.com/