FBT (Fused Biconical Taper) fiber optic splitter for cost-effective signal splitting in single mode networks. Available in 1x2 and 2x2 configurations with steel tube and ABS box packages. 10-year warranty with stable performance across -40°C to +85°C operating range. For more parameters, please. Fused Biconic Taper (FBT) coupler, also be called FBT splitter, based on the traditional technology, it is to bundle to-gether two or more optical fibers, and then pull the cone machine melt stretching, and real-time monitoring the change of the ratio, spectral ratio requirements after melt. hen a small split configuration is needed. All optical fibers used in Wirewerks FBT splitte s are bend insensitive ITU-T G. A very precise and high tech produc-tion will allow the splitting of the signal to be equal ratios ( the frequency bands of 1310±40 nm, 1490±10 nm, and 15.