Roller Tables are Massage tables that DO NOT have the ability to lower or raise the rollers. These tables can NOT be billed to insurance companies because of the lack of this feature. Roller Table's only have one motor that moves the roller back and forth. IST Tables have 3 motors and require higher amperage loads, so the IST tables require heavier duty parts to make them function. See below for a picture of a Roller Table vs a IST table..