The Parallel Guide System greatly enhances the capability of the Festool Guide Rail System by providing a faster, easier, smarter way to create consistent rip cuts. The Parallel Guide Extensions connect to the Parallel Guide (495717), enabling narrow rip cuts from 1mm to 195mm (1/16" to 7-11/16"). The Parallel Guide Extensions must be used in conjunction with the Parallel Guide. The best value is purchasing these two components as a set (P00108). Parallel Guide and Guide Rail sold separately.