Festool FSK Guide Rails offer 250mm, 420mm, or 670mm cutting lengths. For use with Festool TS 60 K, HK 55, and HKC 55 Carpentry Circular Saws. Stop system for accurately repeated angled cuts. Retract function returns the saw to start position after sawing. The compound mitre saw system makes work easier with fast, guided and precisely-angled cross cuts.