The Three-Window Coupler Module (STWCM) from Anylink Technology is a Fiber Optic Coupler with Excess Loss 0.3 to 0.9 dB, Insertion Loss <7.2 to 21.6 dB, Bandwidth ±10 nm, ±40 nm, Wavelength 1310 nm, 1490 nm, 1550 nm, Polarization Dependent Loss <0.3 to 0.7 dB. More details for Three-Window Coupler Module (STWCM) can be seen below.