Quick answer: Bend-insensitive fiber (ITU-T G. 657) is singlemode fiber that maintains low loss when bent to radii as tight as 5-7. 5 mm (vs 30 mm for standard G. A2 as the default for FTTH drop cables, indoor patch cords, and MDU wiring. Proper bend radius control ensures the integrity of optical performance and protects the glass. Corning ClearCurve® drop cables are part of a product family developed to solve the challenges associated with multidwelling unit (MDU) deployments. Smaller and. Bend-insensitive fiber engineers this problem out, allowing the cable to wrap around staples, route into wall plates, and survive the rough handling of FTTH installation without losing the link. temperature changes, UV radiation and to certain extend also chemical attacks. Thus the cables are generally designed to provide high tensile strength, crush resistance and to withstand temperature changes between -40°C and +70°C with attenuation changes as low as possible.