Coherent NuSENSOR bend-insensitive single-mode fibers are highly engineered to be micro and macro bend resistant for Raman, Brillouin and FBG based temperature and strain measurements at 1550 nm. These 0.12 NA, bend-insensitive single-mode fibers provide tight tolerance optical and geometrical specifications measured at the application critical wavelengths. The fiber comes with either a polyimide or mid-temperature acrylate coating and are also available with a hermetic carbon layer. The hermetically carbon-coated layer is immune to the damaging effects of hydrogen ingression, enabling distributed temperature and strain sensing in harsh environments where high H2 partial pressure and elevated temperatures up to 300°C are present.