The 1×2 1310 & 1490nm Dual Window Singlemode FBT Coupler Splitter With Steel Tube is a high-performance optical splitting device designed for stable and accurate power distribution across both the 1310 nm and 1490 nm wavelength windows. Utilizing advanced Fused Biconical Taper (FBT) technology, this splitter ensures low insertion loss, high splitting accuracy, and excellent wavelength stability, making it ideal for FTTx, PON, and multi-wavelength communication systems.