Gordon--on Al's behalf, the LS 25 is an Incra fence. The "LS" stands for Lead Screw, which is the current model of Incra positioners, and the "25" is the working range of that particular positioner in inches. Adding table saw rails for mounting creates a "TS-LS" system (Table Saw-Lead Screw). One could put a TS-LS on the table saw, detach the positioner and use it on a drill press, router table, radial arm saw, etc.
Incra only markets the TS-LS package in 32" and 52" configurations, but if a person has the 25" positioner, the rails and mounting carriage could be bought from Incra for mounting to a table saw. Since various "stops" can be set on the table saw rails, the 25" positioner would not be a handicap at all for use on both a router table and table saw. (not that Al intends to, i was just using that as an example of the flexibility of the systems)
Hope that helps!!
earl