This video presentation describes the FLEX-GUARD Laser Fiber and Sheath and System that helps extend the life of KARL STORZ FLEX-XC or FLEX-X2 Flexible Ureteroscopes. It does this by safeguarding the working channel from mechanical and thermal damage — two causes of significant scope repairs. The FLEX-GUARD comes preassembled with a ScopeSafe laser fiber and protective sheath. The ScopeSafe laser fibers with patented optical filter technology help prevent laser energy from entering the cladding at the interface, insulating the scope channel from thermal damage. This design facilitates multiple passes of the fiber through a deflected scope, simplifying the procedure.