The 1×2 1490 & 1550nm Dual Window Singlemode FBT Coupler Splitter With ABS Box is a high-precision optical power-splitting device engineered for reliable performance across the 1490 nm (E-band) and 1550 nm (C-band) wavelength windows. Manufactured using advanced Fused Biconical Taper (FBT) technology, this splitter delivers low insertion loss, accurate split ratios, excellent wavelength stability, and consistent optical characteristics for dual-wavelength fiber-optic communication systems.