Estink 🤣🤣🤣

Those look exactly like the Incra bars except in aluminum, though the zoo says aluminum alloy and then says stainless steel). Don't see any form of ball bearings, just the expanding nylon washers.

I haven't looked for slides in eons, surprised at the variety now available.
My wider-than-standard Unisaw is unable to best use the design as the adjustment range (of the Incra) is not enough, but these appear to be a decent and inexpensive way to make some jigs that fit a slot without the usual headaches and expense of other aftermarket stuff.