Festool 495717 Parallel Guides For FS Guide Rail System Greatly enhances the Guide Rail System by providing a faster, easier, smarter way to make consistent rip cuts Attaches easily and clamps quickly to the guide rail, ensuring secure and consistent cuts Easy to read scale for cuts up to 650mm ( 25 19/32 in) Easily calibrated against the guide rail splinterguard for precise, splinterfree and consistent ripping Fits all Festool guide rails.