I got this off a craigslist add a few years ago.
It’s old school with oil bath bearings.
And tracking adjusters on both sides of the idler roller.
The disk sander table has a really terrible angle adjuster, a screw wedge, but it also has two support arms that help lock the table in position.
It has worked well for me although the belt has a tendency to drift.
The problem was pretty bad until the rubber sleeve on the idler roller disintegrated due to dry rot.
I decided to replace it with pieces of an old 3×21 belt sander belt that had come apart.
That has reduced the belt drift quite a bit, probably because the gap acts as a self-center.
-- Pete, "It isn't broken, you just aren't using it right."